Si tiene una pregunta, compruebe primero las preguntas frecuentes. En la parte inferior encontrará cómo hacer otras preguntas, solicitar funcionalidades y reportar errores.
Si el asistente de configuración rápida falla, necesitará configurar manualmente una cuenta (para recibir correo electrónico) y una identidad (para enviar correo electrónico). Para esto necesitarás las direcciones IMAP y SMTP y números de puerto, si SSL/TLS o STARTTLS deben ser usados y su nombre de usuario (generalmente, pero no siempre, su dirección de correo electrónico) y su contraseña.
En algunos casos necesitará habilitar el acceso externo a su cuenta y/o utilizar una contraseña especial de aplicación, por ejemplo cuando la autenticación de dos factores esté habilitada.
* Cambiar contraseña: Configuración, configuración manual y más opciones, toque Cuentas, toque cuenta, cambiar contraseña
* Establecer una firma: Configuración, configuración manual y más opciones, identidades de toque, identidad de toque, identidad de toque, firma de edición.
* Añadir dirección CC y CCO: toque el icono de la persona al final del asunto
* Ir al mensaje siguiente/anterior en archivar/eliminar: en la configuración de comportamiento desactive *Cerrar conversaciones automáticamente* y seleccione *Ir a la siguiente/anterior conversación* para *Al cerrar una conversación*
* Añadir una carpeta a la bandeja de entrada unificada: mantenga presionada la carpeta en la lista de carpetas y marque *Mostrar en la bandeja de entrada unificada*
* Añadir una carpeta al menú de navegación: mantenga presionada la carpeta en la lista de carpetas y marque *Mostrar en el menú de navegación*
* Eliminar un mensaje, omitiendo la papelera: en el menú de 3 puntos justo encima del texto del mensaje *Eliminar* o, alternativamente, desmarque la carpeta de la papelera en la configuración de la cuenta
* ~~Un [error en Android 5.1 y 6](https://issuetracker.google.com/issues/37054851) hace que las aplicaciones muestren a veces un formato de hora incorrecto. Cambiar la configuración de Android *Usar formato de 24 horas* podría resolver temporalmente el problema. Una solución fue añadida.~~
* ~~~Un [error en Google Drive](https://issuetracker.google.com/issues/126362828) hace que los archivos exportados a Google Drive estén vacíos. Google ha corregido esto.~~
* ~~Un [error en AndroidX](https://issuetracker.google.com/issues/78495471) hace que FairEmail ocasionalmente se cierre al mantener presionado o deslizar. Google ha corregido esto.~~
* ~~Un [error en AndroidX ROOM](https://issuetracker.google.com/issues/138441698) causa a veces un cierre con "*... Excepción al computar datos en vivo de base de datos ... No se pudo leer la fila...*". Se añadió una solución alternativa.~~
* Un [error en Android](https://issuetracker.google.com/issues/119872129) hace que FairEmail falle con "*... Notificación errónea publicada ...*" en algunos dispositivos una vez después de actualizar FairEmail y pulsar en una notificación.
* Un [error en Android](https://issuetracker.google.com/issues/62427912) ocasiona a veces un error con "*... ActivityRecord no encontrado para ...*" después de actualizar FairEmail. Reinstalando ([fuente](https://stackoverflow.com/questions/46309428/android-activitythread-reportsizeconfigurations-causes-app-to-freeze-with-black)) podría solucionar el problema.
* Un [error en Android](https://issuetracker.google.com/issues/37018931) ocasiona a veces un error con *... InputChannel no está inicializado ...* en algunos dispositivos.
* ~~Un [error en LineageOS](https://review.lineageos.org/c/LineageOS/android_frameworks_base/+/265273) causa a veces un error con *... java.lang.ArrayIndexOutOfBoundsException: length=...; index=... ...*.~~
* Un error en Nova Launcher en Android 5.x hace que FairEmail falle con un *java.lang.StackOverflowError* cuando Nova Launcher tiene acceso al servicio de accesibilidad.
* ~~El selector de carpetas a veces no muestra carpetas por razones desconocidas. Esto parece estar arreglado.~~
* ~~Un [error en AndroidX](https://issuetracker.google.com/issues/64729576) hace difícil agarrar el desplazamiento rápido. Una solución fue añadida.~~
* ~~El cifrado con YubiKey resulta en un bucle infinito. Esto parece ser causado por un [error en OpenKeychain](https://github.com/open-keychain/open-keychain/issues/2507).~~
* Desplazar a una ubicación vinculada internamente en mensajes originales no funciona. Esto no se puede arreglar porque la vista original del mensaje está contenida en una vista de desplazamiento.
* La vista previa del texto de los mensajes no aparece (siempre) en los relojes de Samsung porque [setLocalOnly](https://developer.android.com/reference/androidx/core/app/NotificationCompat.Builder.html#setLocalOnly(boolean)) parece ser ignorado. Se sabe que los textos de vista previa de los mensajes se muestran correctamente en los wearables Pebble 2, Fitbit Charge 3, Mi band 3 y Xiaomi Amazfit BIP. Ver también [estas Preguntas Frecuentes](#user-content-faq126).
* Un [error en Android 6.0](https://issuetracker.google.com/issues/37068143) causa un error con *... Offset inválido: ... El rango válido es ...* cuando el texto está seleccionado y se toca fuera del texto seleccionado. Este error ha sido corregido en Android 6.0.1.
* Los enlaces internos (anchor) no funcionarán porque los mensajes originales se muestran en una WebView embebida en una vista de desplazamiento (la lista de conversaciones). Esta es una limitación de Android que no se puede arreglar o eludir.
* ~~Seleccionar imágenes locales para firmas~~ (esto no se añadirá porque requiere administración de archivos de imagen y porque las imágenes no se muestran por defecto en la mayoría de los clientes de correo electrónico)
* ~~Mostrar mensajes que coincidan con una regla~~
* ~~[ManageSieve](https://tools.ietf.org/html/rfc5804)~~ (no hay librerías Java mantenidas con una licencia adecuada y sin dependencias y, además, FairEmail tiene sus propias reglas de filtro)
* ~~Buscar mensajes con/sin archivos adjuntos~~ (esto no puede ser añadido porque IMAP no soporta la búsqueda de archivos adjuntos)
* ~~Buscar una carpeta~~ (filtrar una lista jerárquica de carpetas es problemático)
* ~~[Mensaje de configuración de autocifrado](https://autocrypt.org/autocrypt-spec-1.0.0.pdf) (sección 4.4)~~ (en mi opinión no es una buena idea permitir que un cliente de correo electrónico maneje claves de cifrado sensibles para un caso de uso excepcional mientras que OpenKeychain también puede exportar claves)
* ~~Carpetas unificadas genéricas~~
* ~~Nuevo programa de notificación de mensajes por cuenta~~ (implementado añadiendo una condición de tiempo a las reglas para que los mensajes puedan ser pospuestos durante los periodos seleccionados)
* ~~Copiar cuentas e identidades~~
* ~~Zoom via pellizco~~ (no es posible en una lista de desplazamiento; la vista completa del mensaje puede ser agrandada en su lugar)
* ~~Vista de carpetas más compacta~~
* ~~Componer listas y tablas~~ (requiere un editor de texto enriquecido, vea [estas FAQ](#user-content-faq99))
El diseño está basado en muchas discusiones y si lo deseas puedes unirte a la discusión [en este foro](https://forum.xda-developers.com/android/apps-games/source-email-t3824168). El objetivo del diseño es ser minimalista (sin menús innecesarios, botones, etc.) y no distraer (colores brillantes, animaciones, etc.). Todas las cosas mostradas deben ser útiles de una u otra manera y deben posicionarse cuidadosamente para un uso fácil. Fuentes, tamaños, colores, etc debe seguir el diseño material siempre que sea posible.
* [(58) ¿Qué significa un icono de correo electrónico abierto/cerrado?](#user-content-faq58)
* [(59) ¿Pueden abrirse mensajes originales en el navegador?](#user-content-faq59)
* [(60) ¿Sabía que ...?](#user-content-faq60)
* [(61) ¿Por qué algunos mensajes se muestran atenuados?](#user-content-faq61)
* [(62) ¿Cuáles métodos de autenticación están soportados?](#user-content-faq62)
* [(63) ¿Cómo se redimensionan las imágenes para mostrarlas en pantalla?](#user-content-faq63)
* [~~(64) ¿Puedes añadir acciones personalizadas para deslizar hacia la izquierda/derecha?~~](#user-content-faq64)
* [(65) ¿Por qué algunos archivos adjuntos se muestran atenuados?](#user-content-faq65)
* [(66) ¿Está FairEmail disponible en la Biblioteca de la Familia de Google Play?](#user-content-faq66)
* [(67) ¿Cómo puedo posponer las conversaciones?](#user-content-faq67)
* [~~(68) ¿Por qué el lector Adobe Acrobat no puede abrir archivos adjuntos PDF / aplicaciones de Microsoft no pueden abrir documentos adjuntos?~~](#user-content-faq68)
* [(69) ¿Puedes añadir desplazamiento automático hasta arriba en un nuevo mensaje?](#user-content-faq69)
* [(70) ¿Cuándo se expandirán automáticamente los mensajes?](#user-content-faq70)
* [(71) ¿Cómo uso las reglas de filtro?](#user-content-faq71)
* [(72) ¿Qué son las cuentas o identidades principales?](#user-content-faq72)
* [(73) ¿Es seguro/eficiente mover mensajes a través de cuentas?](#user-content-faq73)
* *tiene acceso a la red completa* (INTERNET): para enviar y recibir correo electrónico
* *ver conexiones de red* (ACCESS_NETWORK_STATE): para monitorizar los cambios de conectividad a Internet
* *ejecutar al inicio* (RECEIVE_BOOT_COMPLETED): para iniciar la monitorización al iniciar el dispositivo
* *servicio de primer plano* (FOREGROUND_SERVICE): para ejecutar un servicio de primer plano en Android 9 Pie y posterior, ver también la siguiente pregunta
* *evitar que el dispositivo duerme* (WAKE_LOCK): para mantener el dispositivo despierto mientras sincroniza los mensajes
* *facturación in-app* (BILLING): para permitir compras en la app
* Opcional: *lee tus contactos* (READ_CONTACTS): para autocompletar direcciones y para mostrar fotos
* Opcional: *lee el contenido de tu tarjeta SD* (READ_EXTERNAL_STORAGE): para aceptar archivos de otras aplicaciones desactualizadas, consulta también [este FAQ](#user-content-faq49)
* Opcional: *usar hardware de huella dactilar* (USE_FINGERPRINT) y usar *hardware biométrico* (USE_BIOMETRIC): para usar autenticación biométrica
* Opcional: *encontrar cuentas en el dispositivo* (GET_ACCOUNTS) para seleccionar una cuenta cuando se utiliza la configuración rápida de Gmail
* Android 5. Lollipop y antes: *usar cuentas en el dispositivo* (USE_CREDENTIALS): para seleccionar una cuenta al usar la configuración rápida de Gmail (no solicitada en versiones posteriores de Android)
* Android 5. Lollipop y antes: *usar cuentas en el dispositivo* (USE_CREDENTIALS): para seleccionar una cuenta al usar la configuración rápida de Gmail (no solicitada en versiones posteriores de Android)
[Permisos opcionales](https://developer.android.com/training/permissions/requesting) son compatibles con Android 6 Marshmallow y sólo posteriores. En versiones anteriores de Android se le pedirá que conceda los permisos opcionales para instalar FairEmail.
Los siguientes permisos son necesarios para mostrar el recuento de mensajes no leídos como una insignia (ver también [este FAQ](#user-content-faq106)):
FairEmail mantendrá una lista de direcciones de las que recibe y a las que envía mensajes y utilizará esta lista para sugerencias de contactos cuando no se otorgue permiso de contactos a FairEmail. Esto significa que puede utilizar FairEmail sin el proveedor de contactos Android (libreta de direcciones). Ten en cuenta que todavía puedes elegir contactos sin conceder sus permisos a FairEmail, solo sugerir que los contactos no funcionarán sin los permisos de contactos.
Una notificación permanente de baja prioridad con el número de cuentas monitoreadas y el número de operaciones pendientes (ver la siguiente pregunta) se muestra para evitar que Android mate el servicio que se encarga de recibir correo electrónico continuamente. Esto [ya era necesario](https://developer.android.com/reference/android/app/Service.html#startForeground(int,%20android.app.Notification)), pero con la introducción de [modo doze](https://developer.android.com/training/monitoring-device-state/doze-standby) en Android 6 Marshmallow esto es más necesario que nunca. El modo Doze detendrá todas las aplicaciones cuando la pantalla esté apagada por algún tiempo a menos que la aplicación inicie un servicio de primer plano, lo que requiere mostrar una notificación en la barra de estado.
La mayoría, si no todas, otras aplicaciones de correo electrónico no muestran una notificación, con el "efecto secundario" de que los mensajes nuevos a menudo no son reportados o son reportados tarde y que los mensajes no son enviados o son enviados tarde.
Android muestra primero los iconos de las notificaciones de la barra de estado de alta prioridad y ocultará el icono de la notificación de FairEmail si ya no hay espacio para mostrar los iconos. En la práctica esto significa que la notificación de la barra de estado no ocupa espacio en la barra de estado, a menos que haya espacio disponible.
* Android 8 Oreo y posteriores: toque el botón *Canal de recepción* y desactive el canal a través de la configuración de Android (esto no deshabilitará las notificaciones de nuevos mensajes)
* Android 7 Nougat y antes: habilite *Usa el servicio de segundo plano para sincronizar mensajes*, pero asegúrese de leer el comentario debajo de la configuración
Puede cambiar a sincronización periódica de mensajes en la configuración de recepción para eliminar la notificación, pero tenga en cuenta que esto podría aumentar el uso de batería. Vea [aquí](#user-content-faq39) para más detalles sobre el uso de la batería.
Android 8 Oreo también podría mostrar una notificación de barra de estado con el texto *Las aplicaciones se están ejecutando en segundo plano*. Por favor, consulte [aquí](https://www.reddit.com/r/Android/comments/7vw7l4/psa_turn_off_background_apps_notification/) sobre cómo puede desactivar esta notificación.
Algunas personas sugirieron usar [Firebase Cloud Messaging](https://firebase.google.com/docs/cloud-messaging/) (FCM) en lugar de un servicio Android con una notificación en la barra de estado, pero esto requeriría que los proveedores de correo enviaran mensajes FCM o un servidor central donde todos los mensajes sean recogidos enviando mensajes FCM. La primera no va a suceder y la última tendría importantes implicaciones en materia de privacidad.
**(3) ¿Qué son las operaciones y por qué están pendientes?**
La notificación de la barra de estado de baja prioridad muestra el número de operaciones pendientes, que pueden ser:
* *añadir*: añadir mensaje a la carpeta remota
* *mover*: mover mensaje a otra carpeta remota
* *copiar*: copiar mensaje a otra carpeta remota
* *obtener*: obtención de mensajes cambiados (pushed)
* *borrar*: borrar mensaje de la carpeta remota
* *visto*: marcar mensaje como leído/no leído en la carpeta remota
* *respondido*: marca el mensaje como respondido en la carpeta remota
* *marcar*: añadir/remover estrella en la carpeta remota
* *palabra clave*: añadir/eliminar marca IMAP en carpeta remota
* *etiqueta*: establecer/restablecer etiqueta Gmail en carpeta remota
* *encabezados*: descargar encabezados de mensajes
* *raw*: descargar mensaje raw
* *cuerpo*: descargar texto del mensaje
* *adjunto*: descargar adjunto
* *sincronizar*: sincronizar mensajes locales y remotos
* *suscribir*: suscribirse a la carpeta remota
* *purgar*: borrar todos los mensajes de la carpeta remota
* *enviar*: enviar mensaje
* *existe*: comprueba si el mensaje existe
* *regla*: ejecutar regla en el cuerpo del texto
Las operaciones sólo se procesan cuando hay una conexión al servidor de correo electrónico o cuando se sincroniza manualmente. Ver también [estas Preguntas Frecuentes](#user-content-faq16).
Esto puede ser causado por el uso de un nombre de host incorrecto, así que primero compruebe el nombre del host en la configuración avanzada de la identidad/cuenta (pulse Configuración manual y más opciones). Consulte la documentación del proveedor de correo electrónico sobre el nombre de host correcto.
Debería intentar arreglar esto poniéndose en contacto con su proveedor u obteniendo un certificado de seguridad válido porque los certificados de seguridad inválidos son insecuros y permiten [ataques de intermediario](https://en.wikipedia.org/wiki/Man-in-the-middle_attack). Si el dinero es un obstáculo, puede obtener certificados de seguridad gratuitos de [Let's Encrypt](https://letsencrypt.org).
Tenga en cuenta que las versiones antiguas de Android podrían no reconocer las nuevas autoridades de certificación como Let’s Encrypt que causan que las conexiones se consideren inseguras, ver también [aquí](https://developer.android.com/training/articles/security-ssl).
*... java.security.cert.CertPathValidatorException: Trust anchor for certification path not found ...* significa que el administrador de confianza por defecto de Android no pudo verificar la cadena de certificados del servidor.
Su nombre de usuario y contraseña y todos los mensajes serán enviados y recibidos sin cifrar, el cual es **muy inseguro** porque un [ataque de intermediario](https://en.wikipedia.org/wiki/Man-in-the-middle_attack) es muy simple en una conexión no cifrada.
Si aún quiere usar un certificado de seguridad invalido, una contraseña vacía o una conexión de texto simple necesitará habilitar conexiones inseguras en la cuenta y/o configuraciones de identidad. STARTTLS debería ser seleccionado para conexiones de texto simple. Si activa conexiones inseguras, sólo debería conectarse a través de redes privadas y confiables y nunca a través de redes públicas, como las ofrecidas en hoteles, aeropuertos, etc.
* *Bandeja de entrada unificada*: para desactivar la bandeja de entrada unificada y para listar las carpetas seleccionadas para la bandeja de entrada unificada en su lugar
* *Mostrar detalles de dirección por defecto*: para expandir la sección de direcciones por defecto
* *Mostrar automáticamente el mensaje original para los contactos conocidos*: para mostrar automáticamente los mensajes originales para los contactos en su dispositivo, por favor lea [estas Preguntas Frecuentes](#user-content-faq35)
* *Mostrar automáticamente el mensaje original para los contactos conocidos*: para mostrar automáticamente los mensajes originales para los contactos en su dispositivo, por favor lea [estas Preguntas Frecuentes](#user-content-faq35)
Tenga en cuenta que los mensajes sólo se pueden previsualizar cuando se haya descargado el texto del mensaje. Los textos de mensajes más grandes no se descargan por defecto en redes medidas (generalmente móviles). Puede cambiar esto en los ajustes de conexión.
Si utiliza la versión Play Store o GitHub de FairEmail, puede utilizar el asistente de configuración rápida para configurar fácilmente una cuenta e identidad de Gmail. El asistente de configuración rápida de Gmail no está disponible para versiones de terceros, como la compilación de F-Droid porque Google aprobó el uso de OAuth sólo para compilaciones oficiales.
Si no quiere usar una cuenta Gmail del dispositivo, puede habilitar el acceso para "aplicaciones menos seguras" y utilizar la contraseña de su cuenta (no recomendado) o habilitar la autenticación de dos factores y utilizar una contraseña específica de la aplicación. Para utilizar una contraseña necesitará configurar una cuenta e identidad a través de la configuración manual en lugar del asistente de configuración rápida.
**Importante**: Las cuentas de Gsuite autorizadas con un nombre de usuario/contraseña dejarán de funcionar [en un futuro próximo](https://gsuiteupdates.googleblog.com/2019/12/less-secure-apps-oauth-google-username-password-incorrect.html).
Vea [aquí](https://support.google.com/accounts/answer/6010255) acerca de cómo habilitar "aplicaciones menos seguras" o vaya [directamente a la configuración](https://www.google.com/settings/security/lesssecureapps).
Tenga en cuenta que necesita salir de la pantalla de ajustes de "aplicaciones menos seguras" usando la flecha hacia atrás para aplicar la configuración.
Si usa este método, debería usar una [contraseña fuerte](https://en.wikipedia.org/wiki/Password_strength) para su cuenta de Gmail, lo cual es una buena idea de todos modos. Tenga en cuenta que usar el protocolo IMAP [estándar](https://tools.ietf.org/html/rfc3501) en sí mismo no es menos seguro.
Cuando "aplicaciones menos seguras" no está activado, obtendrá el error *La autenticación falló - credenciales inválidas* para cuentas (IMAP) y *Nombre de usuario y contraseña no aceptados* para identidades (SMTP).
Puede obtener la alerta "*Inicie sesión a través de su navegador web*". Esto sucede cuando Google considera que la red que lo conecta a Internet (esto podría ser una VPN) es insegura. Esto se puede evitar usando el asistente de configuración rápida de Gmail o una contraseña específica de la aplicación.
Mire [aquí](https://support.google.com/mail/answer/7126229) las instrucciones de Google y [aquí](https://support.google.com/mail/accounts/answer/78754) para solucionar problemas.
Los mensajes enviados normalmente se mueven de la bandeja de salida a la carpeta enviados tan pronto como su proveedor agrega los mensajes enviados a la carpeta enviados. Esto requiere que se seleccione una carpeta enviados en la configuración de la cuenta y que la carpeta enviados se configure para sincronizar.
Algunos proveedores no llevan un seguimiento de los mensajes enviados o el servidor SMTP utilizado podría no estar relacionado con el proveedor. En estos casos FairEmail automáticamente añadirá mensajes enviados a la carpeta enviados al sincronizar la carpeta enviados, lo que sucederá después de que se haya enviado un mensaje. Tenga en cuenta que esto resultará en tráfico extra de Internet.
~~Si esto no sucede, es posible que su proveedor no esté al tanto de los mensajes enviados o que esté utilizando un servidor SMTP no relacionado con el proveedor.~~ ~~En estos casos puede habilitar la configuración avanzada de identidad *Guardar mensajes enviados* para que FairEmail añada mensajes enviados a la carpeta enviados justo después de enviar un mensaje.~~~~Tenga en cuenta que habilitar este ajuste puede resultar en mensajes duplicados si su proveedor añade mensajes enviados a la carpeta enviados.~~~~Además tenga cuidado de que habilitar esta configuración dará como resultado un uso adicional de datos, especialmente cuando se envíen mensajes con grandes archivos adjuntos.~~
~~Si los mensajes enviados en la bandeja de salida no se encuentran en la carpeta enviados en una sincronización completa, también se moverán de la bandeja de salida a la carpeta enviados.~~ ~~Una sincronización completa ocurre al reconectar al servidor o al sincronizar periódicamente o manualmente.~~~~Probablemente querrá habilitar la configuración avanzada *Almacenar mensajes enviados* en su lugar para mover mensajes a la carpeta enviados más pronto.~~
Puede utilizar una cuenta de Microsoft Exchange si es accesible a través de IMAP, lo que es usualmente el caso. Vea [aquí](https://support.office.com/en-us/article/what-is-a-microsoft-exchange-account-47f000aa-c2bf-48ac-9bc2-83e5c6036793) para más información.
Por favor consulte [aquí](https://support.office.com/en-us/article/pop-imap-and-smtp-settings-for-outlook-com-d088b986-291d-42b8-9564-9c414e2aa040) la documentación de Microsoft acerca de la configuración de un cliente de correo electrónico. También hay una sección sobre errores de conexión comunes y soluciones.
Algunas versiones antiguas del servidor Exchange tienen un error que causa mensajes vacíos y adjuntos corruptos. Consulte [estas Preguntas Frecuentes](#user-content-faq110) para una solución provisional.
Algunos proveedores le permiten tener múltiples alias. Puede configurarlos estableciendo el campo de dirección de correo electrónico de una identidad adicional a la dirección de alias y configurando el campo nombre de usuario a su dirección de correo electrónico principal.
Alternativamente, puede habilitar *Permitir editar la dirección del remitente* en la configuración avanzada de una identidad existente para editar el nombre de usuario cuando se compone un nuevo mensaje, si su proveedor lo permite.
FairEmail actualizará automáticamente las contraseñas de las identidades relacionadas cuando actualice la contraseña de la cuenta asociada o una identidad relacionada.
~~El mensaje de error *UIDPLUS no soportado* significa que su proveedor de correo no proporciona la extensión IMAP [UIDPLUS](https://tools.ietf.org/html/rfc4315). Esta extensión IMAP es necesaria para implementar la sincronización de dos vías, que no es una característica opcional. Así que, a menos que su proveedor pueda habilitar esta extensión, no puede usar FairEmail para este proveedor.~~
~~Además de que cualquier proveedor de correo electrónico decente soporta [IMAP](https://en.wikipedia.org/wiki/Internet_Message_Access_Protocol) estos días,~~ ~~usar [POP](https://en.wikipedia.org/wiki/Post_Office_Protocol) dará como resultado un uso adicional innecesario de la batería y un retraso en las notificaciones de nuevos mensajes.~~~~Además, POP es inadecuado para la sincronización de dos vías y la mayoría de las veces la gente lee y escribe mensajes en diferentes dispositivos hoy en día.~~
~~Básicamente, POP sólo soporta descargar y borrar mensajes de la bandeja de entrada.~~ ~~Entonces, las operaciones comunes como configurar los atributos del mensaje (leer, marcar, responder, etc.), añadir (respaldar) y mover mensajes no es posible.~~
~~Por ejemplo [Gmail puede importar mensajes](https://support.google.com/mail/answer/21289) desde otra cuenta POP,~~ ~~que puede ser usado como solución temporal para cuando su proveedor no soporta IMAP.~~
La comunicación con los servidores de correo electrónico siempre está cifrada, a menos que lo desactive explícitamente. Esta pregunta se refiere al cifrado opcional de extremo a extremo con PGP o S/MIME. El remitente y destinario primero deberían acordar esto e intercambiar mensajes firmados para transferir su clave pública para poder enviar mensajes cifrados.
Para firmar/cifrar un mensaje, simplemente seleccione el método apropiado en el diálogo de enviar. También puede abrir el diálogo de enviar usando el menú de tres puntos en caso de que haya seleccionado *No volver a mostrar* anteriormente.
Para verificar una firma o descifrar un mensaje recibido, abra el mensaje y pulse el icono de gesto o candado justo debajo de la barra de acción del mensaje.
La primera vez que envíe un mensaje firmado/cifrado puede que le pidan una clave de firma. FairEmail almacenará automáticamente la clave de firma seleccionada en la identidad utilizada para la próxima vez. Si necesita restablecer la clave de firma, simplemente guarde la identidad o mantenga pulsada la identidad en la lista de identidades y seleccione *Restablecer clave de firma*. La clave de firma seleccionada es visible en la lista de identidades. Si es necesario seleccionar una clave para cada caso puede crear múltiples identidades para la misma cuenta con la misma dirección de correo electrónico.
En la configuración de privacidad puede seleccionar el método de cifrado predeterminado (PGP o S/MIME), active *Firmar por defecto*, *Cifrar por defecto* y *Descifrar mensajes automáticamente*, pero tenga en cuenta que el descifrado automático no es posible si la interacción del usuario es requerida, como seleccionar una clave o leer un token de seguridad.
El texto/adjuntos a cifrar y el texto/adjunto descifrados se almacenan localmente sólo y nunca se añadirán al servidor remoto. Si quiere deshacer el descifrado, puedes usar el elemento de menú *Resincronizar* en el menú de tres puntos de la barra de acción del mensaje.
Necesitará instalar y configurar [OpenKeychain](https://f-droid.org/en/packages/org.sufficientlysecure.keychain/) primero. FairEmail ha sido probado con OpenKeychain versión 5.4. Es muy probable que las versiones posteriores sean compatibles, pero las versiones anteriores podrían no serlo.
**Importante**: la aplicación OpenKeychain es conocida por cerrarse (silenciosamente) cuando la aplicación que le llama (FairEmail) no está autorizada aún y está recibiendo una clave pública existente. Puede solucionar esto intentando enviar un mensaje firmado/cifrado a un remitente con una clave pública desconocida.
**Importante**: si la aplicación OpenKeychain (ya) no puede encontrar una clave, puede que deba restablecer una clave previamente seleccionada. Esto se puede hacer manteniendo presionada una identidad en la lista de identidades (ajustes, configuración manual y más opciones, identidades).
**Importante**: para permitir que aplicaciones como FairEmail se conecten de forma confiable al servicio OpenKeychain para cifrar/descifrar mensajes, podría ser necesario desactivar las optimizaciones de batería para la aplicación OpenKeychain.
**Importante**: en algunas versiones / dispositivos Android es necesario habilitar *Mostrar ventanas emergentes mientras se ejecuta en segundo plano* en los permisos adicionales de la configuración de la aplicación Android de la aplicación OpenKeychain. Sin este permiso el borrador será guardado, pero la ventana emergente de OpenKeychain para confirmar/seleccionar podría no aparecer.
FairEmail enviará el encabezado [Autocrypt](https://autocrypt.org/) para su uso por otros clientes de correo electrónico, pero sólo para mensajes firmados y cifrados porque demasiados servidores de correo tienen problemas con el a menudo largo encabezado Autocrypt. Tenga en cuenta que la forma más segura de iniciar un intercambio de correo electrónico cifrado es enviar primero los mensajes firmados. Los encabezados de Autocrypt recibidos serán enviados a la aplicación OpenKeychain para ser almacenados al verificar una firma o desencriptar un mensaje.
Todo el manejo de las llaves se delega a la aplicación de la cadena OpenKey por razones de seguridad. Esto también significa que FairEmail no almacena claves PGP.
Se admite cifrado PGP embebido en los mensajes recibidos, pero las firmas PGP embebidas y PGP embebido en los mensajes salientes no son soportados, mire [aquí](https://josefsson.org/inline-openpgp-considered-harmful.html) sobre por qué no.
* *Sin clave*: no hay ninguna clave PGP disponible para una de las direcciones de correo electrónico listadas
* *Falta la clave para el cifrado*: probablemente hay una clave seleccionada en FairEmail que ya no existe en la aplicación OpenKeychain. Restablecer la clave (ver arriba) probablemente solucione este problema.
Las claves privadas son almacenadas por Android y pueden ser importadas a través de la configuración de seguridad avanzada de Android. Hay un atajo (botón) para esto en la configuración de privacidad. Android le pedirá que establezca un PIN, patrón o contraseña si no lo ha hecho antes. Si tiene un dispositivo Nokia con Android 9, por favor [lea esto primero](https://nokiamob.net/2019/08/10/a-bug-prevents-nokia-1-owners-from-unlocking-their-screen-even-with-right-pin-pattern/).
Tenga en cuenta que los certificados pueden contener múltiples claves para múltiples propósitos, por ejemplo para la autenticación, el cifrado y la firma. Android sólo importa la primera clave, así que para importar todas las claves, el certificado primero debe ser dividido. Esto no es muy trivial y se le aconseja que pida ayuda al proveedor del certificado.
Nótese que la firma S/MIME con otros algoritmos que RSA es soportada, pero tenga en cuenta que otros clientes de correo electrónico tal vez no lo soporten. El cifrado S/MIME es posible únicamente con algoritmos simétricos, lo que significa que en la práctica se utiliza RSA.
El método de cifrado por defecto es PGP, pero el último método de cifrado utilizado será recordado para la identidad seleccionada para la próxima vez. Puede que necesite activar las opciones de envío en el menú de tres puntos de nuevo para poder seleccionar el método de cifrado.
Para permitir diferentes claves privadas para la misma dirección de correo electrónico, FairEmail siempre le permitirá seleccionar una clave cuando haya múltiples identidades con la misma dirección de correo electrónico para la misma cuenta.
Las claves públicas son almacenadas por FairEmail y pueden ser importadas al verificar una firma por primera vez o a través de la configuración de privacidad (formatos PEM o DER).
* *No se ha encontrado ningún certificado que coincida con targetContraints*: esto seguramente significa que está usando una versión antigua de FairEmail
* *incapaz de encontrar una ruta de certificación válida para el objetivo solicitado*: básicamente esto significa que uno o más certificados intermedios o raíz no fueron encontrados
* *La clave privada no coincide con ninguna clave de cifrado*: la clave seleccionada no puede utilizarse para descifrar el mensaje, probablemente porque es la clave incorrecta
* *No hay clave privada*: no se ha seleccionado ningún certificado o no hay ningún certificado disponible en el almacén de claves Android
En caso de que la cadena de certificados sea incorrecta, puede pulsar el pequeño botón de información para mostrar todos los certificados. Después de los detalles del certificado se muestra el emisor o "auto-Firmado". Un certificado es auto-Firmado cuando el sujeto y el emisor son los mismos. Los certificados de una autoridad certificadora (CA) están marcados con "[keyCertSign](https://tools.ietf.org/html/rfc5280#section-4.2.1.3)". Los certificados encontrados en el almacén de claves Android están marcados con "Android".
Tenga en cuenta que una cadena de certificados siempre será inválida cuando no se pueda encontrar ningún certificado raíz en el almacén de claves Android, que es fundamental para la validación del certificado S/MIME.
Si está buscando un certificado S/MIME gratuito (de prueba), consulte [aquí](http://kb.mozillazine.org/Getting_an_SMIME_certificate) para ver las opciones. Por favor, asegúrese de [leer esto antes](https://davidroessli.com/logs/2019/09/free-smime-certificates-in-2019/#update20191219) si desea solicitar un certificado de S/MIME Actalis. Si está buscando un certificado S/MIME barato, he tenido buena experiencia con [Certum](https://www.certum.eu/en/smime-certificates/).
Puede empezar a buscar mensajes en el remitente (de), destinatario (a, cc, cco), asunto, palabras clave o texto de mensaje mediante el uso de la lupa en la barra de acción de una carpeta. También puede buscar desde cualquier aplicación seleccionando *Buscar en FairEmail* en el menú emergente.
Buscar en la bandeja de entrada unificada buscará en todas las carpetas de todas las cuentas, buscar en la lista de carpetas sólo buscará en la cuenta asociada y buscar en una carpeta sólo buscará en esa carpeta.
Los mensajes se buscarán primero en el dispositivo. Habrá un botón de acción con un icono de buscar de nuevo en la parte inferior para continuar la búsqueda en el servidor. Puede seleccionar en qué carpeta continuar la búsqueda.
El protocolo IMAP no permite buscar en más de una carpeta al mismo tiempo. Buscar en el servidor es una operación costosa, por lo tanto no es posible seleccionar múltiples carpetas.
La búsqueda de mensajes locales no distingue mayúsulas/minúsculas y es sobre texto parcial. El texto del mensaje de los mensajes locales no se buscará si el texto del mensaje no se ha descargado todavía. Buscar en el servidor puede ser sensible a mayúsculas o minúsculas y puede estar en texto parcial o palabras enteras, dependiendo del proveedor.
Algunos servidores no pueden manejar la búsqueda en el texto del mensaje cuando hay un gran número de mensajes. Para este caso hay una opción para desactivar la búsqueda en el texto del mensaje.
Es posible usar operadores de búsqueda de Gmail prefijando un comando de búsqueda con *raw:*. Si ha configurado sólo una cuenta de Gmail, puede iniciar una búsqueda directa directamente en el servidor buscando desde la bandeja de entrada unificada. Si configuró varias cuentas de Gmail, primero tendrá que navegar a la lista de carpetas o a la carpeta de archivo (todos los mensajes) de la cuenta de Gmail en la que quiere buscar. Por favor, [vea aquí](https://support.google.com/mail/answer/7190) para los posibles operadores de búsqueda. Por ejemplo:
* [sqlite](https://www.sqlite.org/), el motor de base de datos de Android tiene un límite de tamaño de registro, evitando que los mensajes de texto se almacenen en la base de datos
* Las aplicaciones Android tienen memoria limitada para trabajar, incluso si el dispositivo tiene suficiente memoria disponible
Esto significa que la búsqueda de un texto de mensaje requiere que los archivos que contengan los textos del mensaje deban abrirse uno por uno para comprobar si el texto buscado está contenido en el archivo, que es un proceso relativamente costoso.
En la *configuración miscelánea* puede habilitar *Construir índice de búsqueda* para aumentar significativamente la velocidad de búsqueda en el dispositivo, pero tenga en cuenta que esto aumentará el uso de la batería y el espacio de almacenamiento. El índice de búsqueda se basa en palabras, por lo que no es posible buscar texto parcial. La búsqueda usando el índice de búsqueda es por defecto Y, así que buscar *manzana naranja* buscará manzana Y naranja. Las palabras separadas por comas resultan en la búsqueda de O, así que por ejemplo *manzana, naranja* buscará manzana O naranja. Ambos se pueden combinar, así que buscar *manzana, naranja banana* buscará manzana O (naranja Y banana). Usar el índice de búsqueda es una característica pro.
Search expressions can be used for searching on the device via the search index and for searching on the email server, but not for searching on the device without search index for performance reasons.
To use an Outlook, Live or Hotmail account with two factor authentication enabled, you need to create an app password. See [here](https://support.microsoft.com/en-us/help/12409/microsoft-account-app-passwords-two-step-verification) for the details.
See [here](https://support.office.com/en-us/article/pop-imap-and-smtp-settings-for-outlook-com-d088b986-291d-42b8-9564-9c414e2aa040) for Microsoft's instructions.
The message header and message body are fetched separately from the server. The message text of larger messages is not being pre-fetched on metered connections and will be fetched on demand on expanding a message. The message text will keep loading if there is no connection to the account, see also the next question, or if there other operations, like synchronizing messages, are being executed.
You can check the account and folder list for the account and folder state (see the legend for the meaning of the icons) and the operation list accessible via the main navigation menu for pending operations (see [this FAQ](#user-content-faq3) for the meaning of the operations).
If FairEmail is holding off because of prior connectivity issues, please see [this FAQ](#user-content-faq123), you can force synchronization via the three dots menu.
So, check your account and folder settings and check if the accounts/folders are connected (see the legend in the navigation menu for the meaning of the icons).
Some Android versions stop apps and services too aggressively. See [this dedicated website](https://dontkillmyapp.com/) and [this Android issue](https://issuetracker.google.com/issues/122098785) for more information.
In case of successive connection errors, FairEmail will hold off increasingly longer to not drain the battery of your device. This is described in [this FAQ](#user-content-faq123).
Also note that most free apps will appear not to be sustainable in the end, whereas FairEmail is properly maintained and supported, and that free apps may have a catch, like sending privacy sensitive information to the internet.
I have been working on FairEmail almost every day for more than two years, so I think the price is more than reasonable. For this reason there won't be discounts either.
If a purchased pro feature doesn't work as intended and this isn't caused by a problem in the free features and I cannot fix the problem in a timely manner, you can get a refund. In all other cases there is no refund possible. In no circumstances there is a refund possible for any problem related to the free features, since there wasn't paid anything for them and because they can be evaluated without any limitation. I take my responsibility as seller to deliver what has been promised and I expect that you take responsibility for informing yourself of what you are buying.
Android 8 Oreo and later: please see [here](https://developer.android.com/training/notify-user/channels) about how to configure notification channels. You can use the button *Default channel* in the notification settings of the app to directly go to the right Android notification channel settings.
Tenga en cuenta que las aplicaciones ya no pueden cambiar los ajustes de notificación, incluyendo la configuración de la luz de notificación, en Android 8 Oreo y posteriores.
A veces es necesario desactivar la configuración *Mostrar vista previa del mensaje en las notificaciones* o habilitar *Mostrar notificaciones sólo con un texto de vista previa* para evitar un error en Android. Esto podría aplicarse también a los sonidos y vibración de notificaciones.
FairEmail intentará reconectarse automáticamente después de un retraso. Este retraso se duplicará tras cada intento fallido de evitar que se agote la batería y que se bloquee permanentemente el acceso.
El error *... La autenticación falló ...* o *... AUTHENTICATE falló...* probablemente significa que su nombre de usuario o contraseña era incorrecto. Algunos proveedores esperan como nombre de usuario sólo *nombre de usuario* y otros su dirección de correo electrónico completa *nombredeusuario@ejemplo.com*. Al copiar/pegar para introducir un nombre de usuario o contraseña, pueden copiarse caracteres invisibles, lo que también podría causar este problema. También se sabe que algunos administradores de contraseñas hacen esto incorrectamente. El nombre de usuario puede ser sensible a mayúsculas, así que intente sólo caracteres en minúsculas. La contraseña es casi siempre sensible a mayúsculas y minúsculas. Algunos proveedores requieren usar una contraseña de aplicación en lugar de la contraseña de la cuenta, así que por favor revise la documentación del proveedor. A veces es necesario habilitar primero el acceso externo (IMAP/SMTP) en el sitio web del proveedor. Otras posibles causas son que la cuenta está bloqueada o que el inicio de sesión ha sido restringido administrativamente de alguna manera, por ejemplo permitiendo iniciar sesión desde ciertas redes / direcciones IP solamente.
El error *... Demasiados intentos de autenticación incorrectos ...* probablemente significa que está utilizando una contraseña de cuenta Yahoo en lugar de una contraseña de la aplicación. Por favor, consulte [estas Preguntas Frecuentes](#user-content-faq88) sobre cómo configurar una cuenta Yahoo.
El mensaje *... +OK ...* probablemente significa que un puerto POP3 (normalmente el número de puerto 995) está siendo usado para una cuenta IMAP (normalmente el puerto número 993).
Los errores *... saludo inválido ...*, *... requiere una dirección válida ...* y *... Parámetro HELO no se ajusta a la sintaxis RFC ...* puede resolverse cambiando la configuración de identidad avanzada *Utilice la dirección IP local en lugar del nombre de host*.
El error *... No se pudo conectar al host ...* significa que no hubo respuesta del servidor de correo en un tiempo razonable (20 segundos por defecto). Esto indica principalmente problemas de conectividad a internet, posiblemente causados por una VPN o por una aplicación de firewall. Puede intentar aumentar el tiempo de espera de conexión en la configuración de conexión de FairEmail, para cuando el servidor de correo es realmente lento.
El error *... Conexión rechazada...* significa que el servidor de correo electrónico o algo entre el servidor de correo y la aplicación, como un cortafuegos, rechazó activamente la conexión.
El error *... Red inaccesible ...* significa que el servidor de correo electrónico no fue accesible a través de la conexión a internet actual, por ejemplo, porque el tráfico de internet sólo está restringido al tráfico local.
El error *... Host no resuelto ...*, *... No se puede resolver el host ...* o *... Ninguna dirección asociada con el nombre de host ...* significa que la dirección del servidor de correo electrónico no se pudo resolver en una dirección IP. Esto puede ser causado por un VPN, un bloqueador de anuncios o un servidor [DNS](https://en.wikipedia.org/wiki/Domain_Name_System) que no esté funcionando apropiadamente (local).
El error *... Software causó fin de conexión ...* significa que el servidor de correo o algo entre FairEmail y el servidor de correo terminó activamente una conexión existente. Esto puede suceder, por ejemplo, cuando la conectividad se perdió abruptamente. Un ejemplo típico es activar el modo avión.
Los errores *... BYE Cerrando sesión...*, *... Conexión restablecida...* significa que el servidor de correo o algo entre el servidor de correo y la aplicación, por ejemplo un router o un firewall (app), ha terminado activamente una conexión existente.
El error *... Conexión cerrada por el par ...* podría ser causada por un servidor de Exchange no actualizado, vea [aquí](https://blogs.technet.microsoft.com/pki/2010/09/30/sha2-and-windows/) para más información.
Los errores *... Error de lectura ...*, *... Error de escritura ...*, *... Tiempo de lectura agotado ...*, *... Broken pipe ...* mean that the email server is not responding anymore or that the internet connection is bad.
The error *... Connection dropped by server? ...* means that the email server unexpectedly terminated the connection. This sometimes happen when there were too many connections in a too short time or when a wrong password was used for too many times. In this case, please make sure your password is correct and disable receiving in the receive settings for about 30 minutes and try again. If needed, see [this FAQ](#user-content-faq23) about how you can reduce the number of connections.
The warning *... Unsupported encoding ...* means that the character set of the message is unknown or not supported. FairEmail will assume ISO-8859-1 (Latin1), which will in most cases result in showing the message correctly.
Please [see here](#user-content-faq4) for the errors *... Untrusted ... not in certificate ...*, *... Invalid security certificate (Can't verify identity of server) ...* or *... Trust anchor for certification path not found ...*
Many public Wi-Fi networks block outgoing email to prevent spam. Sometimes you can workaround this by using another SMTP port. See the documentation of the provider for the usable port numbers.
If you are using a [VPN](https://en.wikipedia.org/wiki/Virtual_private_network), the VPN provider might block the connection because it is too aggressively trying to prevent spam. Note that [Google Fi](https://fi.google.com/) is using a VPN too.
SMTP servers can reject messages for [a variety of reasons](https://en.wikipedia.org/wiki/List_of_SMTP_server_return_codes). Too large messages and triggering the spam filter of an email server are the most common reasons.
* El límite de tamaño del archivo adjunto para Gmail [es de 25 MB](https://support.google.com/mail/answer/6584)
* El límite de tamaño de archivo adjunto para Outlook y Office 365 [es de 20 MB](https://support.microsoft.com/en-us/help/2813269/attachment-size-exceeds-the-allowable-limit-error-when-you-add-a-large)
* El límite de tamaño del archivo adjunto para Yahoo [es de 25 MB](https://help.yahoo.com/kb/SLN5673.html)
* *554 5.7.1 Servicio no disponible; Host cliente xxxx.xx.xx.xxx bloqueado*, por favor [vea aquí](https://docs.gandi.net/en/gandimail/faq/error_types/554_5_7_1_service_unavailable.html)
* *501 Error de sintaxis - línea demasiado larga* es a menudo causada por el uso de un encabezado Autocrypt largo
* *503 5.5.0 Destinatario ya especificado* significa principalmente que una dirección está siendo utilizada como dirección A y CC
* *554 5.7.1 ... no se permite transmitir* significa que el servidor de correo electrónico no reconoce el nombre de usuario/dirección de correo electrónico. Por favor, compruebe el nombre de host y el nombre de usuario/dirección de correo electrónico en la configuración de identidad.
* *550 Spam message rejected because IP is listed by ...* means that the email server rejected to send a message from the current (public) network address because it was misused to send spam by (hopefully) somebody else before. Please try to enable flight mode for 10 minutes to acquire a new network address.
* *550 We're sorry, but we can't send your email. Either the subject matter, a link, or an attachment potentially contains spam, or phishing or malware.* means that the email provider considers an outgong message as harmful.
* *571 5.7.1 Message contains spam or virus or sender is blocked ...* means that the email server considered an outgoing message as spam. This probably means that the spam filters of the email server are too strict. You'll need to contact the email provider for support on this.
* Verifique su dirección de correo electrónico [aquí](https://mail.google.com/mail/u/0/#settings/accounts) (necesitará utilizar un navegador de escritorio para esto)
La autorización de las cuentas de Gmail configuradas con el asistente de configuración rápida deben actualizarse periódicamente a través del [administrador de cuentas de Android](https://developer.android.com/reference/android/accounts/AccountManager). This requires contact/account permissions and internet connectivity.
The error *... Authentication failed ... network error ...* means that the Android account manager was not able to refresh the authorization of a Gmail account due to problems with the internet connection
The error *... Authentication failed ... Credenciales inválidas ...* podría ser causado al cambiar la contraseña de la cuenta o al haber revocado los permisos de cuenta/contactos requeridos. In case the account password was changed, you'll need to authenticate the Google account in the Android account settings again. En caso de que los permisos hayan sido revocados, puede iniciar el asistente de configuración rápida de Gmail para conceder los permisos necesarios de nuevo (no necesita configurar la cuenta de nuevo).
The eror *... ServiceDisabled ...* might be caused by enrolling in the [Advanced Protection Program](https://landing.google.com/advancedprotection/): "*To read your email, you can (must) use Gmail - You won’t be able to use your Google Account with some (all) apps & services that require access to sensitive data like your emails*", see [here](https://support.google.com/accounts/answer/7519408?hl=en&ref_topic=9264881).
An easy way to configure periodically checking for messages for all folders except the inbox is to use *Apply to all ...* in the three-dots menu of the folder list and to tick the bottom two advanced checkboxes.
The maximum number of simultaneous folder connections for Gmail is 15, so you can synchronize at most 15 folders simultaneously on *all* your devices at the same time. For this reason Gmail *user* folders are set to poll by default instead of synchronize always. When needed or desired, you can change this by long pressing a folder in the folder list and selecting *Edit properties*. See [here](https://support.google.com/mail/answer/7126229) for details.
When using a Dovecot server, you might want to change the setting [mail_max_userip_connections](https://doc.dovecot.org/settings/dovecot_core_settings/#mail-max-userip-connections).
Note that it will take the email server a while to discover broken connections, for example due to going out of range of a network, which means that effectively only half of the folder connections are available. For Gmail this would be just 7 connections.
Browse messages on the server will fetch messages from the email server in real time when you reach the end of the list of synchronized messages, even when the folder is set to not synchronize. You can disable this feature in the advanced account settings.
When a menu item to select/open/save a file is disabled (dimmed) or when you get the message *Storage access framework not available*, the [storage access framework](https://developer.android.com/guide/topics/providers/document-provider), a standard Android component, is probably not present. This might be because your custom ROM does not include it or because it was actively removed (debloated).
FairEmail does not request storage permissions, so this framework is required to select files and folders. No app, except maybe file managers, targeting Android 4.4 KitKat or later should ask for storage permissions because it would allow access to *all* files.
The storage access framework is provided by the package *com.android.documentsui*, which is visible as *Files* app on some Android versions (notable OxygenOS).
If you would like your name or alias to be included in the list of contributors in *About* the app, please [contact me](https://contact.faircode.eu/?product=fairemailsupport).
Note that downloading external images from a remote server can be used to record you did see a message, which you likely don't want if the message is spam or malicious.
On Android 8.0 Oreo and later you can manage the properties of the individual notification channels, for example to set a specific notification sound or to show notifications on the lock screen.
See [here](https://developer.android.com/guide/topics/ui/notifiers/notifications#ManageChannels) for details on notification channels. In short: tap on the notification channel name to access the channel settings.
Just long press a folder, select *Edit properties*, and enable either *Show in unified inbox* or *Notify new messages* (available on Android 7 Nougat and later only) and tap *Save*.
Quick settings require Android 7.0 Nougat or later. The usage of settings tiles is explained [here](https://support.google.com/android/answer/9083864).
Identities are as expected matched by account. For incoming messages the *to*, *cc*, *bcc*, *from* and *(X-)delivered/envelope/original-to* addresses will be checked (in this order) and for outgoing messages (drafts, outbox and sent) only the *from* addresses will be checked. Equal addresses have precedence over partially matching addresses, except for *delivered-to* addresses.
Matching will be done only once on receiving a message, so changing the configuration will not change existing messages. You could clear local messages by long pressing a folder in the folder list and synchronize the messages again though.
It is possible to configure a [regex](https://en.wikipedia.org/wiki/Regular_expression) in the identity settings to match **the username** of an email address (the part before the @ sign).
If you like to match the special purpose email addresses abc@example.com and xyx@example.com and like to have a fallback email address main@example.com as well, you could do something like this:
Matched identities can be used to color code messages. The identity color takes precedence over the folder and account color. Setting identity colors is a pro feature.
Viewing remotely stored images (see also [this FAQ](#user-content-faq27)) and opening links might not only tell the sender that you have seen the message, but will also leak your IP address. See also this question: [Why email's link is more dangerous than web search's link?](https://security.stackexchange.com/questions/241139/why-emails-link-is-more-dangerous-than-web-searchs-link).
Opening attachments or viewing an original message might load remote content and execute scripts, that might not only cause privacy sensitive information to leak, but can also be a security risk.
Note that reformatted messages are often better readable than original messages because the margins are removed, and font colors and sizes are standardized.
The Gmail app shows images by default by downloading the images through a Google proxy server. Since the images are downloaded from the source server [in real-time](https://blog.filippo.io/how-the-new-gmail-image-proxy-works-and-what-this-means-for-you/), this is even less secure because Google is involved too without providing much benefit.
All supported Android versions [encrypt all user data](https://source.android.com/security/encryption), so all data, including usernames, passwords, messages, etc, is stored encrypted.
If the device is secured with a PIN, pattern or password, you can make the account and identity passwords visible. If this is a problem because you are sharing the device with other people, consider to use [user profiles](https://www.howtogeek.com/333484/how-to-set-up-multiple-user-profiles-on-android/).
Recent Android versions by default report *app usage* as a percentage in the Android battery settings screen. **Confusingly, *app usage* is not the same as *battery usage* and is not even directly related to battery usage!** The app usage (while in use) will be very high because FairEmail is using a foreground service which is considered as constant app usage by Android. However, this doesn't mean that FairEmail is constantly using battery power. The real battery usage can be seen by navigating to this screen:
As a rule of thumb the battery usage should be below or in any case not be much higher than *Mobile network standby*. If this isn't the case, please turn on *Auto optimize* in the receive settings. If this doesn't help, please [ask for support](https://contact.faircode.eu/?product=fairemailsupport).
If you are comparing the battery usage of FairEmail with another email client, please make sure the other email client is setup similarly. For example comparing always sync (push messages) and (infrequent) periodic checking for new messages is not a fair comparison.
Reconnecting to an email server will use extra battery power, so an unstable internet connection will result in extra battery usage. Also, some email servers prematurely terminate idle connections, while [the standard](https://tools.ietf.org/html/rfc2177) says that an idle connection should be kept open for 29 minutes. In these cases you might want to synchronize periodically, for example each hour, instead of continuously. Note that polling frequently (more than every 30-60 minutes) will likely use more battery power than synchronizing always because connecting to the server and comparing the local and remote messages are expensive operations.
[On some devices](https://dontkillmyapp.com/) it is necessary to *disable* battery optimizations (setup step 3) to keep connections to email servers open. In fact, leaving battery optimizations enabled can result in extra battery usage for all devices, even though this sounds contradictory!
Most of the battery usage, not considering viewing messages, is due to synchronization (receiving and sending) of messages. So, to reduce the battery usage, set the number of days to synchronize message for to a lower value, especially if there are a lot of recent messages in a folder. Long press a folder name in the folders list and select *Edit properties* to access this setting.
Note that you can set the number of days to *keep* messages for to a higher number than to *synchronize* messages for. You could for example initially synchronize messages for a large number of days and after this has been completed reduce the number of days to synchronize messages for, but leave the number of days to keep messages for. After decreasing the number of days to keep messages for, you might want to run the cleanup in the miscellaneous settings to remove old files.
In the receive settings you can enable to always synchronize starred messages, which will allow you to keep older messages around while synchronizing messages for a limited number of days.
Disabling the folder option *Automatically download message texts and attachments* will result in less network traffic and thus less battery usage. You could disable this option for example for the sent folder and the archive.
Synchronizing messages at night is mostly not useful, so you can save on battery usage by not synchronizing at night. In the settings you can select a schedule for message synchronization (this is a pro feature).
FairEmail will by default synchronize the folder list on each connection. Since folders are mostly not created, renamed and deleted very often, you can save some network and battery usage by disabling this in the receive settings.
FairEmail will by default check if old messages were deleted from the server on each connection. If you don't mind that old messages that were delete from the server are still visible in FairEmail, you can save some network and battery usage by disabling this in the receive settings.
Some providers don't follow the IMAP standard and don't keep connections open long enough, forcing FairEmail to reconnect often, causing extra battery usage. You can inspect the *Log* via the main navigation menu to check if there are frequent reconnects (connection closed/reset, read/write error/timeout, etc). You can workaround this by lowering the keep-alive interval in the advanced account settings to for example 9 or 15 minutes. Note that battery optimizations need to be disabled in setup step 3 to reliably keep connections alive.
Some providers send every two minutes something like '*Still here*' resulting in network traffic and your device to wake up and causing unnecessary extra battery usage. You can inspect the *Log* via the main navigation menu to check if your provider is doing this. If your provider is using [Dovecot](https://www.dovecot.org/) as IMAP server, you could ask your provider to change the [imap_idle_notify_interval](https://wiki.dovecot.org/Timeouts) setting to a higher value or better yet, to disable this. If your provider is not able or willing to change/disable this, you should consider to switch to periodically instead of continuous synchronization. You can change this in the receive settings.
If you got the message *This provider does not support push messages* while configuring an account, consider switching to a modern provider which supports push messages (IMAP IDLE) to reduce battery usage.
If your device has an [AMOLED](https://en.wikipedia.org/wiki/AMOLED) screen, you can save battery usage while viewing messages by switching to the black theme.
If auto optimize in the receive settings is enabled, an account will automatically be switched to periodically checking for new messages when the email server:
In addition, the trash and spam folders will be automatically set to checking for new messages after three successive [too many simultaneous connections](#user-content-faq23) errors.
If the connection to the email server is lost, FairEmail will always synchronize the messages again to make sure no messages were missed. If the connection is unstable, this can result in extra data usage. In this case, it is a good idea to decrease the number of days to synchronize messages for to a minimum (see the previous question) or to switch to periodically synchronizing of messages (receive settings).
By default FairEmail does not download message texts and attachments larger than 256 KiB when there is a metered (mobile or paid Wi-Fi) internet connection. You can change this in the connection settings.
The error '*Handshake failed ... WRONG_VERSION_NUMBER ...*' might mean that you are trying to connect to an IMAP or SMTP server without an encrypted connection, typically using port 143 (IMAP) and port 25 (SMTP), or that a wrong protocol (SSL/TLS or STARTTLS) is being used.
If your provider doesn't support encrypted connections, you should ask to make this possible. If this isn't an option, you could enable *Allow insecure connections* both in the advanced settings AND the account/identity settings.
The error '*Handshake failed ... SSLV3_ALERT_ILLEGAL_PARAMETER ...*' is either caused by a bug in the SSL protocol implementation or by a too short DH key on the email server and can unfortunately not be fixed by FairEmail.
The error '*Handshake failed ... HANDSHAKE_FAILURE_ON_CLIENT_HELLO ...*' might be caused by the provider still using RC4, which isn't supported since [Android 7](https://developer.android.com/about/versions/nougat/android-7.0-changes.html#tls-ssl) anymore.
The error '*Handshake failed ... UNSUPPORTED_PROTOCOL or TLSV1_ALERT_PROTOCOL_VERSION ...*' might be caused by enabling hardening connections in the connection settings or by Android not supporting older protocols anymore, like SSLv3.
Android 8 Oreo and later [do not support](https://developer.android.com/about/versions/oreo/android-8.0-changes#security-all) SSLv3 anymore. There is no way to workaround lacking RC4 and SSLv3 support because it has completely been removed from Android (which should say something).
You can use [this website](https://ssl-tools.net/mailservers) or [this website](https://www.immuniweb.com/ssl/) to check for SSL/TLS problems of email servers.
The EFF [writes](https://www.eff.org/nl/deeplinks/2018/06/announcing-starttls-everywhere-securing-hop-hop-email-delivery): "*Additionally, even if you configure STARTTLS perfectly and use a valid certificate, there’s still no guarantee your communication will be encrypted.*"
Show original, shows the original message as the sender has sent it, including original fonts, colors, margins, etc. FairEmail does and will not alter this in any way, except for requesting [TEXT_AUTOSIZING](https://developer.android.com/reference/android/webkit/WebSettings.LayoutAlgorithm), which will *attempt* to make small text more readable.
~~Contact photos and identicons are always shown for the sender because this is necessary for conversation threads.~~ ~~Getting contact photos for both the sender and receiver is not really an option because getting contact photo is an expensive operation.~~
You'll get the message *This key is not available. To use it, you must import it as one of your own!* when trying to decrypt a message with a public key. To fix this you'll need to import the private key.
If you see a 'spinner' at the top of the message list, the folder is still being synchronized with the remote server. You can see the progress of the synchronization in the folder list. See the legend about what the icons and numbers mean.
The speed of your device and internet connection and the number of days to synchronize messages for determine how long synchronization will take. Note that you shouldn't set the number of days to synchronize messages for to more than one day in most cases, see also [this FAQ](#user-content-faq39).
You'll get the error message *No primary account or no drafts folder* when trying to compose a message while there is no account set to be the primary account or when there is no drafts folder selected for the primary account. This can happen for example when you start FairEmail to compose a message from another app. FairEmail needs to know where to store the draft, so you'll need to select one account to be the primary account and/or you'll need to select a drafts folder for the primary account.
This can also happen when you try to reply to a message or to forward a message from an account with no drafts folder while there is no primary account or when the primary account does not have a drafts folder.
~~You'll get the error message *No primary account or no archive folder* when searching for messages from another app. FairEmail needs to know where to search, so you'll need to select one account to be the primary account and/or you'll need to select a archive folder for the primary account.~~
You likely selected or sent an attachment or image with an outdated file manager or an outdated app which assumes all apps still have storage permissions. For security and privacy reasons modern apps like FairEmail have no full access to all files anymore. This can result into the error message *An outdated app sent a file path instead of a file stream* if a file name instead of a file stream is being shared with FairEmail because FairEmail cannot randomly open files.
You can fix this by switching to an up-to-date file manager or an app designed for recent Android versions. Alternatively, you can grant FairEmail read access to the storage space on your device in the Android app settings. Note that this workaround [won't work on Android Q](https://developer.android.com/preview/privacy/scoped-storage) anymore.
See also [question 25](#user-content-faq25) and [what Google writes about it](https://developer.android.com/training/secure-file-sharing/share-file#RespondToRequest).
You can synchronize more or even all messages by long pressing a folder (inbox) in the folder list of an account (tap on the account name in the navigation menu) and selecting *Synchronize more* in the popup menu.
Folders are first sorted on account order (by default on account name) and within an account with special, system folders on top, followed by folders set to synchronize. Within each category the folders are sorted on (display) name. You can set the display name by long pressing a folder in the folder list and selecting *Edit properties*.
There is no reliable way to know if an account connection was terminated gracefully or forcefully. Trying to reconnect to an account while the account connection was terminated forcefully too often can result in problems like [too many simultaneous connections](#user-content-faq23) or even the account being blocked. To prevent such problems, FairEmail waits 90 seconds until trying to reconnect again.
The message action bar works on a single message and the bottom action bar works on all the messages in the conversation. Since there is often more than one message in a conversation, this is not possible. Moreover, there are quite some message specific actions, like forwarding.
Moving the message action bar to the bottom of the message is visually not appealing because there is already a conversation action bar at the bottom of the screen.
Note that there are not many, if any, email apps that display a conversation as a list of expandable messages. This has a lot of advantages, but the also causes the need for message specific actions.
You can use multiple select for this. Long press the first message, don't lift your finger and slide down to the last message. Then use the three dot action button to execute the desired action.
Note that if you switch back to the text editor that not all HTML might be rendered as-is because the Android text editor is not able to render all HTML. Similarly, if you use the text editor, the HTML might be altered in unexpected ways.
If you want to use preformatted text, like [ASCII art](https://en.wikipedia.org/wiki/ASCII_art), you should wrap the text in a *pre* element, like this:
For security reasons the files with the original message texts are not accessible to other apps, so this is not possible. In theory the [Storage Access Framework](https://developer.android.com/guide/topics/providers/document-provider) could be used to share these files, but even Google's Chrome cannot handle this.
* Did you know that starred messages can be synchronized/kept always? (this can be enabled in the receive settings)
* Did you know that you can long press the 'write message' icon to go to the drafts folder?
* Did you know there is an advanced option to mark messages read when they are moved? (archiving and trashing is also moving)
* Did you know that you can select text (or an email address) in any app on recent Android versions and let FairEmail search for it?
* Did you know that FairEmail has a tablet mode? Rotate your device in landscape mode and conversation threads will be opened in a second column if there is enough screen space.
* Did you know that you can long press a reply template to create a draft message from the template?
* Did you know that you can long press, hold and swipe to select a range of messages?
* Did you know that you can retry sending messages by using pull-down-to-refresh in the outbox?
* Did you know that you can swipe a conversation left or right to go to the next or previous conversation?
* Did you know that you can tap on an image to see where it will be downloaded from?
* Did you know that you can long press the folder icon in the action bar to select an account?
* Did you know that you can long press the star icon in a conversation thread to set a colored star?
* Did you know that you can open the navigation drawer by swiping from the left, even when viewing a conversation?
* Did you know that you can long press the people's icon to show/hide the CC/BCC fields and remember the visibility state for the next time?
* Did you know that you can insert the email addresses of an Android contact group via the three dots overflow menu?
* Did you know that if you select text and hit reply, only the selected text will be quoted?
* Did you know that you can long press the trash icons (both in the message and the bottom action bar) to permanently delete a message or conversation? (version 1.1368+)
Messages shown dimmed (grayed) are locally moved messages for which the move is not confirmed by the server yet. This can happen when there is no connection to the server or the account (yet). These messages will be synchronized after a connection to the server and the account has been made or, if this never happens, will be deleted if they are too old to be synchronized.
SASL authentication methods, besides CRAM-MD5, are not supported because [JavaMail for Android](https://javaee.github.io/javamail/Android) does not support SASL authentication.
[Server Name Indication](https://en.wikipedia.org/wiki/Server_Name_Indication) is supported by [all supported Android versions](https://developer.android.com/training/articles/security-ssl).
Large inline or attached [PNG](https://en.wikipedia.org/wiki/Portable_Network_Graphics) and [JPEG](https://en.wikipedia.org/wiki/JPEG) images will automatically be resized for displaying on screens. This is because email messages are limited in size, depending on the provider mostly between 10 and 50 MB. Images will by default be resized to a maximum width and height of about 1440 pixels and saved with a compression ratio of 90 %. Images are scaled down using whole number factors to reduce memory usage and to retain image quality. Automatically resizing of inline and/or attached images and the maximum target image size can be configured in the send settings.
If you want to resize images on a case-by-case basis, you can use [Send Reduced](https://f-droid.org/en/packages/mobi.omegacentauri.SendReduced/) or a similar app.
~~The most natural thing to do when swiping a list entry left or right is to remove the entry from the list.~~ ~~The most natural action in the context of an email app is moving the message out of the folder to another folder.~~~~You can select the folder to move to in the account settings.~~
~~Other actions, like marking messages read and snoozing messages are available via multiple selection.~~ ~~You can long press a message to start multiple selection. See also [this question](#user-content-faq55).~~
~~Swiping left or right to mark a message read or unread is unnatural because the message first goes away and later comes back in a different shape.~~ ~~Note that there is an advanced option to mark messages automatically read on moving,~~~~which is in most cases a perfect replacement for the sequence mark read and move to some folder.~~~~You can also mark messages read from new message notifications.~~
Inline (image) attachments are shown dimmed. [Inline attachments](https://tools.ietf.org/html/rfc2183) are supposed to be downloaded and shown automatically, but since FairEmail doesn't always download attachments automatically, see also [this FAQ](#user-content-faq40), FairEmail shows all attachment types. To distinguish inline and regular attachments, inline attachments are shown dimmed.
The price of the few pro features is too low, lower than the price of most similar apps, and there are [too many fees and taxes](#user-content-faq19), to justify making FairEmail available in the [Google Play Family Library](https://support.google.com/googleone/answer/7007852). Note that Google promotes the Family libray, but lets developers pay for it.
Multiple select one of more conversations (long press to start multiple selecting), tap the three dot button and select *Snooze ...*. Alternatively, in the expanded message view use *Snooze ...* in the message three-dots 'more' menu or the timelapse action in the bottom action bar. Select the time the conversation(s) should snooze and confirm by tapping OK. The conversations will be hidden for the selected time and shown again afterwards. You will receive a new message notification as reminder.
~~Adobe Acrobat reader and Microsoft apps still expects full access to all stored files,~~ ~~while apps should use the [Storage Access Framework](https://developer.android.com/guide/topics/providers/document-provider) since Android KitKat (2013)~~~~to have access to actively shared files only. This is for privacy and security reasons.~~
~~You can workaround this by saving the attachment and opening it from the Adobe Acrobat reader / Microsoft app,~~ ~~but you are advised to install an up-to-date and preferably open source PDF reader / document viewer,~~~~for example one listed [here](https://github.com/offa/android-foss#-document--pdf-viewer).~~
The message list is automatically scrolled up when navigating from a new message notification or after a manual refresh. Always automatically scrolling up on arrival of new messages would interfere with your own scrolling, but if you like you can enable this in the settings.
There is one exception: the message was not downloaded yet and the message is too large to download automatically on a metered (mobile) connection. You can set or disable the maximum message size on the 'connection' settings tab.
New rules will be applied to new messages received in the folder, not to existing messages. You can check the rule and apply the rule to existing messages or, alternatively, long press the rule in the rule list and select *Execute now*.
All the conditions of a rule need to be true for the rule action to be executed. All conditions are optional, but there needs to be at least one condition, to prevent matching all messages. If you want to match all senders or all recipients, you can just use the @ character as condition because all email addresses will contain this character.
Matching is not case sensitive, unless you use [regular expressions](https://en.wikipedia.org/wiki/Regular_expression). Please see [here](https://developer.android.com/reference/java/util/regex/Pattern) for the documentation of Java regular expressions. You can test a regex [here](https://regexr.com/).
Note that [dot all mode](https://developer.android.com/reference/java/util/regex/Pattern#DOTALL) is enabled to be able to match [unfolded headers](https://tools.ietf.org/html/rfc2822#section-3.2.3).
Rules are applied directly after the message header has been fetched, but before the message text has been downloaded, so it is not possible to apply conditions to the message text. Note that large message texts are downloaded on demand on a metered connection to save on data usage.
If you want to forward a message, consider to use the move action instead. This will be more reliable than forwarding as well because forwarded messages might be considered as spam.
Since message headers are not downloaded and stored by default to save on battery and data usage and to save storage space it is not possible to preview which messages would match a header rule condition.
Moving messages across accounts is safe because the raw, original messages will be downloaded and moved and because the source messages will be deleted only after the target messages have been added
Batch moving messages across accounts is efficient if both the source folder and target folder are set to synchronize, else FairEmail needs to connect to the folder(s) for each message.
Some providers, notably Gmail, list all messages in all folders, except trashed messages, in the archive (all messages) folder too. FairEmail shows all these messages in a non obtrusive way to indicate that these messages are in fact the same message.
Gmail allows one message to have multiple labels, which are presented to FairEmail as folders. This means that messages with multiple labels will be shown multiple times as well.
The folder menu *Clear local messages* removes messages from the device which are present on the server too. It does not delete messages from the server. This can be useful after changing the folder settings to not download the message content (text and attachments), for example to save space.
Depending on the speed of your device (processor speed and maybe even more memory speed) messages might be displayed with a small delay. FairEmail is designed to dynamically handle a large number of messages without running out of memory. This means that messages needs to be read from a database and that this database needs to be watched for changes, both of which might cause small delays.
Some convenience features, like grouping messages to display conversation threads and determining the previous/next message, take a little extra time. Note that there is no *the* next message because in the meantime a new message might have been arrived.
When comparing the speed of FairEmail with similar apps this should be part of the comparison. It is easy to write a similar, faster app which just displays a lineair list of messages while possible using too much memory, but it is not so easy to properly manage resource usage and to offer more advanced features like conversation threading.
FairEmail is based on the state-of-the-art [Android architecture components](https://developer.android.com/topic/libraries/architecture/), so there is little room for performance improvements.
In the receive settings you can enable scheduling and set a time period and the days of the week *when* messages should be *received*. Note that an end time equal to or earlier than the start time is considered to be 24 hours later.
Automation, see below, can be used for more advanced schedules, like for example multiple synchronization periods per day or different synchronization periods for different days.
It is possible to install FairEmail in multiple user profiles, for example a personal and a work profile, and to configure FairEmail differently in each profile, which is another possibility to have different synchronization schedules and to synchronize a different set of accounts.
It is also possible to create [filter rules](#user-content-faq71) with a time condition and to snooze messages until the end time of the time condition. This way it is possible to *snooze* business related messages until the start of the business hours. This also means that the messages will be on your device for when there is (temporarily) no internet connection.
Note that recent Android versions allow overriding DND (Do Not Disturb) per notification channel and per app, which could be used to (not) silence specific (business) notifications. Please [see here](https://support.google.com/android/answer/9069335) for more information.
Normally, FairEmail maintains a connection to the configured email servers whenever possible to receive messages in real-time. If you don't want this, for example to be not disturbed or to save on battery usage, just disable receiving in the receive settings. This will stop the background service which takes care of automatic synchronization and will remove the associated status bar notification.
~~The error message *Unable to load BODYSTRUCTURE* is caused by bugs in the email server,~~ ~~see [here](https://javaee.github.io/javamail/FAQ#imapserverbug) for more details.~~
~~The original message is shown as the sender has sent it, including all colors.~~ ~~Changing the background color would not only make the original view not original anymore, it can also result in unreadable messages.~~
Please see [here](https://en.wikipedia.org/wiki/Web_beacon) about what a tracking image exactly is. In short tracking images keep track if you opened a message.
Another use is to generate [shortcuts](#user-content-faq31) on recent Android versions to quickly send a message to frequently contacted people. This is also why the number of times contacted and the last time contacted is being recorded and why you can make a contact a favorite or exclude it from favorites by long pressing it.
The error message *invalid credentials* means either that the user name and/or password is incorrect, for example because the password was changed or expired, or that the account authorization has expired.
If the account authorization has expired, you will have to select the account again. You will likely need to save the associated identity again as well.
The preferred way to set up a Yahoo account is by using the quick setup wizard, which will use OAuth instead of a password and is therefore safer (and easier as well).
By default FairEmail sends each message both as plain text and as HTML formatted text because almost every receiver expects formatted messages these days. If you want/need to send plain text messages only, you can enable this in the advanced identity options. You might want to create a new identity for this if you want/need to select sending plain text messages on a case-by-case basis.
FairEmail will automatically link not linked web links (http and https) and not linked email addresses (mailto) for your convenience. However, texts and links are not easily distinguished, especially not with lots of [top level domains](https://en.wikipedia.org/wiki/List_of_Internet_top-level_domains) being words. This is why texts with dots are sometimes incorrectly recognized as links, which is better than not recognizing some links.
Links for the tel, geo, rtsp and xmpp protocols will be recognized too, but links for less usual or less safe protocols like telnet and ftp will not be recognized. The regex to recognize links is already *very* complex and adding more protocols will make it only slower and possibly cause errors.
~~Synchronizing messages is an expensive proces because the local and remote messages need to be compared,~~ ~~so periodically synchronizing messages will not result in saving battery power, more likely the contrary.~~
Spam filtering, verification of the [DKIM](https://en.wikipedia.org/wiki/DomainKeys_Identified_Mail) signature and [SPF](https://en.wikipedia.org/wiki/Sender_Policy_Framework) authorization is a task of email servers, not of an email client. Servers generally have more memory and computing power, so they are much better suited to this task than battery-powered devices. Also, you'll want spam filtered for all your email clients, possibly including web email, not just one email client. Moreover, email servers have access to information, like the IP address, etc of the connecting server, which an email client has no access to.
Spam filtering based on message headers might have been feasible, but unfortunately this technique is [patented by Microsoft](https://patents.google.com/patent/US7543076).
Recent versions of FairEmail can filter spam to a certain extend using a message classifier. Please see [this FAQ](#user-content-faq163) for more information about this.
Of course you can report messages as spam with FairEmail, which will move the reported messages to the spam folder and train the spam filter of the provider, which is how it is supposed to work. This can be done automatically with [filter rules](#user-content-faq71) too. Blocking the sender will create a filter rule to automatically move future messages of the same sender into the spam folder.
Note that you should not delete spam messages, also not from the spam folder, because the email server uses the messages in the spam folder to "learn" what spam messages are.
Also, FairEmail can show a small red warning flag when DKIM, SPF or [DMARC](https://en.wikipedia.org/wiki/DMARC) authentication failed on the receiving server. You can enable/disable [authentication verification](https://en.wikipedia.org/wiki/Email_authentication) in the display settings.
FairEmail can show a warning flag too if the domain name of the (reply) email address of the sender does not define an MX record pointing to an email server. This can be enabled in the receive settings. Be aware that this will slow down synchronization of messages significantly.
If legitimate messages are failing authentication, you should notify the sender because this will result in a high risk of messages ending up in the spam folder. Moreover, without proper authentication there is a risk the sender will be impersonated. The sender might use [this tool](https://www.mail-tester.com/) to check authentication and other things.
FairEmail uses services and alarms, provides widgets and listens for the boot completed event to be started on device start, so it is not possible to store the app on external storage media, like an sdcard. See also [here](https://developer.android.com/guide/topics/data/install-location).
Messages, attachments, etc stored on external storage media, like an sdcard, can be accessed by other apps and is therefore not safe. See [here](https://developer.android.com/training/data-storage) for the details.
If you need to save on storage space, you can limit the number of days messages are being synchronized and kept for. You can change these settings by long pressing a folder in the folder list and selecting *Edit properties*.
The red/orange stripe at the left side of the header means that the DKIM, SPF or DMARC authentication failed. See also [this FAQ](#user-content-faq92).
For privacy and security reasons FairEmail does not have permissions to directly access files, instead the Storage Access Framework, available and recommended since Android 4.4 KitKat (released in 2013), is used to select files.
If an app is listed depends on if the app implements a [document provider](https://developer.android.com/guide/topics/providers/document-provider). If the app is not listed, you might need to ask the developer of the app to add support for the Storage Access Framework.
Android Q will make it harder and maybe even impossible to directly access files, see [here](https://developer.android.com/preview/privacy/scoped-storage) and [here](https://www.xda-developers.com/android-q-storage-access-framework-scoped-storage/) for more details.
After revoking contacts permissions Android does not allow FairEmail access to your contacts anymore. However, picking contacts is delegated to and done by Android and not by FairEmail, so this will still be possible without contacts permissions.
A [Rich text](https://en.wikipedia.org/wiki/Formatted_text) or [Markdown](https://en.wikipedia.org/wiki/Markdown) editor would not be used by many people on a small mobile device and, more important, Android doesn't support a rich text editor and most rich text editor open source projects are abandoned. See [here](https://forum.xda-developers.com/showpost.php?p=79061829&postcount=4919) for some more details about this.
You can use *Force sync* in the three-dots menu of the unified inbox to let FairEmail synchronize the folder list again and you can long press the folders to enable synchronization.
The dot shows the relative position of the conversation in the message list. The dot will be show orange when the conversation is the first or last in the message list, else it will be blue. The dot is meant as an aid when swiping left/right to go to the previous/next conversation.
Images will automatically be rotated when automatic resizing of images is enabled in the settings (enabled by default). However, automatic rotating depends on the [Exif](https://en.wikipedia.org/wiki/Exif) information to be present and to be correct, which is not always the case. Particularly not when taking a photo with a camara app from FairEmail.
Note that only [JPEG](https://en.wikipedia.org/wiki/JPEG) and [PNG](https://en.wikipedia.org/wiki/Portable_Network_Graphics) images can contain Exif information.
FairEmail will check if the country code of the SIM card and the country code of the network are in the [EU roam-like-at-home countries](https://en.wikipedia.org/wiki/European_Union_roaming_regulations#Territorial_extent) and assumes no roaming if the country codes are equal and the advanced roam-like-at-home option is enabled.
Please [see here](https://github.com/leolin310148/ShortcutBadger#supported-launchers) for a list of launchers which can show the number of unread messages.
Only *new* unread messages in folders set to show new message notifications will be counted, so messages marked unread again and messages in folders set to not show new message notification will not be counted.
Depending on what you want, the notification settings *Let the number of new messages match the number of notifications* needs to be enabled or disabled.
This feature depends on support of your launcher. FairEmail merely 'broadcasts' the number of unread messages using the ShortcutBadger library. If it doesn't work, this cannot be fixed by changes in FairEmail.
Some launchers display '1' for [the monitoring notification](#user-content-faq2), despite FairEmail explicitly requesting not to show a badge for this notification. This could be caused by a bug in the launcher app or in your Android version. Please double check if the notification dot is disabled for the receive (service) notification channel. You can go to the right notification channel settings via the notification settings of FairEmail. This might not be obvious, but you can tap on the channel name for more settings.
You can set a colored star via the *more* message menu, via multiple selection (started by long pressing a message), by long pressing a star in a conversation or automatically by using [rules](#user-content-faq71).
You need to know that colored stars are not supported by the IMAP protocol and can therefore not be synchronized to an email server. This means that colored stars will not be visible in other email clients and will be lost on downloading messages again. However, the stars (without color) will be synchronized and will be visible in other email clients, when supported.
Some email clients use IMAP keywords for colors. However, not all servers support IMAP keywords and besides that there are no standard keywords for colors.
~~When you delete messages from a folder the messages will be moved to the trash folder, so you have a chance to restore the messages.~~ ~~You can permanently delete messages from the trash folder.~~~~Permanently delete messages from other folders would defeat the purpose of the trash folder, so this will not be added.~~
~~Using *select account* to select and authorize Google accounts require special permission from Google for security and privacy reasons.~~ ~~This special permission can only be acquired for apps a developer manages and is responsible for.~~~~Third party builds, like the F-Droid builds, are managed by third parties and are the responsibility of these third parties.~~~~So, only these third parties can acquire the required permission from Google.~~~~Since these third parties do not actually support FairEmail, they are most likely not going to request the required permission.~~
~~Using *select account* in third party builds is not possible in recent versions anymore.~~ ~~In older versions this was possible, but it will now result in the error *UNREGISTERED_ON_API_CONSOLE*.~~
Empty messages and/or corrupt attachments are probably being caused by a bug in the server software. Older Microsoft Exchange software is known to cause this problem. Mostly you can workaround this by disabling *Partial fetch* in the advanced account settings:
After disabling this setting, you can use the message 'more' (three dots) menu to 'resync' empty messages. Alternatively, you can *Delete local messages* by long pressing the folder(s) in the folder list and synchronize all messages again.
OAuth for Gmail is supported via the quick setup wizard. The Android account manager will be used to fetch and refresh OAuth tokens for selected on-device accounts. OAuth for non on-device accounts is not supported because Google requires a [yearly security audit](https://support.google.com/cloud/answer/9110914) ($15,000 to $75,000) for this. You can read more about this [here](https://www.theregister.com/2019/02/11/google_gmail_developer/).
There are plenty of email providers to choose from. Which email provider is best for you depends on your wishes/requirements. Please see the websites of [Restore privacy](https://restoreprivacy.com/secure-email/) or [Privacy Tools](https://www.privacytools.io/providers/email/) for a list of privacy oriented email providers with advantages and disadvantages.
Some providers, like ProtonMail, Tutanota, use proprietary email protocols, which make it impossible to use third party email apps. Please see [this FAQ](#user-content-faq129) for more information.
If your device has a biometric sensor, for example a fingerprint sensor, you can enable/disable biometric authentication in the navigation (hamburger) menu of the settings screen. When enabled FairEmail will require biometric authentication after a period of inactivity or after the screen has been turned off while FairEmail was running. Activity is navigation within FairEmail, for example opening a conversation thread. The inactivity period duration can be configured in the miscellaneous settings. When biometric authentication is enabled new message notifications will not show any content and FairEmail won't be visible on the Android recents screen.
Biometric authentication is meant to prevent others from seeing your messages only. FairEmail relies on device encryption for data encryption, see also [this FAQ](#user-content-faq37).
The format of the settings files of most other email apps is not documented, so this is difficult. Sometimes it is possible to reverse engineer the format, but as soon as the settings format changes things will break. Also, settings are often incompatible. For example, FairEmail has unlike most other email apps settings for the number of days to synchronize messages for and for the number of days to keep messages for, mainly to save on battery usage. Moreover, setting up an account/identity with the quick setup wizard is simple, so it is not really worth the effort.
Email address [chips](https://material.io/design/components/chips.html) look nice, but cannot be edited, which is quite inconvenient when you made a typo in an email address.
Chips are not suitable for showing in a list and since the message header in a list should look similar to the message header of the message view it is not an option to use chips for viewing messages.
~~Contacts in the Android contacts list are considered to be known and trusted,~~ ~~unless the contact is in the group / has the label '*Untrusted*' (case insensitive).~~
You can also try to clear the cache of the Play store app via the Android apps settings. Restarting the device might be necessary to let the Play store recognize the purchase correctly.
* If you get *ITEM_ALREADY_OWNED*, the Play store app probably needs to be updated, please [see here](https://support.google.com/googleplay/answer/1050566?hl=en)
* Purchases are stored in the Google cloud and cannot get lost
* There is no time limit on purchases, so they cannot expire
* Google does not expose details (name, e-mail, etc) about buyers to developers
* An app like FairEmail cannot select which Google account to use
* It may take a while until the Play store app has synchronized a purchase to another device
* Play Store purchases cannot be used without the Play Store, which is also not allowed by Play Store rules
~~The widget is designed to look good on most home/launcher screens by making it monochrome and by using a half transparent background.~~ ~~This way the widget will nicely blend in, while still being properly readable.~~
New message notifications will be removed on swiping notifications away or on marking the associated messages read. Opening the app will not remove new message notifications. This gives you a choice to leave new message notifications as a reminder that there are still unread messages.
On Android 7 Nougat and later new message notifications will be [grouped](https://developer.android.com/training/notify-user/group). Tapping on the summary notification will open the unified inbox. The summary notification can be expanded to view individual new message notifications. Tapping on an individual new message notification will open the conversation the message it is part of. See [this FAQ](#user-content-faq70) about when messages in a conversation will be auto expanded and marked read.
FairEmail groups messages based on the standard *Message-ID*, *In-Reply-To* and *References* headers. FairEmail does not group on other criteria, like the subject, because this could result in grouping unrelated messages and would be at the expense of increased battery usage.
~~The recipient name and/or email address in the addresses section will be shown in a warning color~~ ~~when the sender domain name and the domain name of the *to* address do not match.~~~~Mostly this indicates that the message was received *via* an account with another email address.~~
If FairEmail cannot connect to an email server to synchronize messages, for example if the internet connection is bad or a firewall or a VPN is blocking the connection, FairEmail will retry two times after waiting 4 and 8 seconds while keeping the device awake (=use battery power). If this fails, FairEmail will schedule an alarm to retry after 15, 30 and eventually every 60 minutes and let the device sleep (=no battery usage).
Note that [Android doze mode](https://developer.android.com/training/monitoring-device-state/doze-standby) does not allow to wake the device earlier than after 15 minutes.
Sending messages will be retried on connectivity changes only (reconnecting to the same network or connecting to another network) to prevent the email server from blocking the connection permanently. You can pull down the outbox to retry manually.
Note that sending will not be retried in case of authentication problems and when the server rejected the message. In this case you can pull down the outbox to try again.
The message *Message too large or too complex to display* will be shown if there are more than 100,000 characters or more than 500 links in a message. Reformatting and displaying such messages will take too long. You can try to use the original message view, powered by the browser, instead.
Directly after the first step new messages will be notified. However, only until after the second step the message text will be available. FairEmail updates exiting notifications with a preview of the message text, but unfortunately wearable notifications cannot be updated.
Since there is no guarantee that a message text will always be fetched directly after a message header, it is not possible to guarantee that a new message notification with a preview text will always be sent to a wearable.
If you think this is good enough, you can enable the notification option *Only send notifications with a message preview to wearables* and if this does not work, you can try to enable the notification option *Show notifications with a preview text only*. Note that this applies to wearables not showing a preview text too, even when the Android Wear app says the notification has been sent (bridged).
If you want to have the full message text sent to your wearable, you can enable the notification option *Preview all text*. Note that some wearables are known to crash with this option enabled.
If you use a Samsung wearable with the Galaxy Wearable (Samsung Gear) app, you might need to enable notifications for FairEmail when the setting *Notifications*, *Apps installed in the future* is turned off in this app.
The error *... Syntactically invalid HELO argument(s) ...* means that the SMTP server rejected the local IP address or host name. You can likely fix this error by enabling or disabling the advanced indentity option *Use local IP address instead of host name*.
ProtonMail uses a proprietary email protocol and [does not directly support IMAP](https://protonmail.com/support/knowledge-base/imap-smtp-and-pop3-setup/), so you cannot use FairEmail to access ProtonMail.
Tutanota uses a proprietary email protocol and [does not support IMAP](https://tutanota.com/faq/#imap), so you cannot use FairEmail to access Tutanota.
The warning *No server found at ...* means that there was no email server registered at the indicated domain name. Replying to the message might not be possible and might result in an error. This could indicate a falsified email address and/or spam.
The error *... ParseException ...* means that there is a problem with a received message, likely caused by a bug in the sending software. FairEmail will workaround this is in most cases, so this message can mostly be considered as a warning instead of an error.
The error *...SendFailedException...* means that there was a problem while sending a message. The error will almost always include a reason. Common reasons are that the message was too big or that one or more recipient addresses were invalid.
The warning *Message too large to fit into the available memory* means that the message was larger than 10 MiB. Even if your device has plenty of storage space Android provides limited working memory to apps, which limits the size of messages that can be handled.
If you read from left to right, swiping to the left will show the next message. Similarly, if you read from right to left, swiping to the right will show the next message.
There is a bug in some Android versions causing [setOnlyAlertOnce](https://developer.android.com/reference/android/app/Notification.Builder#setOnlyAlertOnce(boolean)) to mute notifications. Since FairEmail shows new message notifications right after fetching the message headers and FairEmail needs to update new message notifications after fetching the message text later, this cannot be fixed or worked around by FairEmail.
The Microsoft Exchange ActiveSync protocol [is patented](https://en.wikipedia.org/wiki/Exchange_ActiveSync#Licensing) and can therefore not be supported. For this reason you won't find many, if any, other email clients supporting ActiveSync.
The Microsoft Exchange Web Services protocol [is being phased out](https://techcommunity.microsoft.com/t5/Exchange-Team-Blog/Upcoming-changes-to-Exchange-Web-Services-EWS-API-for-Office-365/ba-p/608055).
Note that the desciption of FairEmail starts with the remark that non-standard protocols, like Microsoft Exchange Web Services and Microsoft ActiveSync are not supported.
Since the IMAP protocol is meant to synchronize two ways, deleting a message from the device would result in fetching the message again when synchronizing again.
However, FairEmail supports hiding messages, either via the three-dots menu in the action bar just above the message text or by multiple selecting messages in the message list. Basically this is the same as "leave on server" of the POP3 protocol with the advantage that you can show the messages again when needed.
Individual messages will rarely be trashed and mostly this happens by accident. Showing trashed messages in conversations makes it easier to find them back.
You can permanently delete a message using the message three-dots *delete* menu, which will remove the message from the conversation. Note that this irreversible.
Similarly, drafts are shown in conversations to find them back in the context where they belong. It is easy to read through the received messages before continuing to write the draft later.
Calendar and contact management can better be done by a separate, specialized app. Note that FairEmail is a specialized email app, not an office suite.
Also, I prefer to do a few things very well, instead of many things only half. Moreover, from a security perspective, it is not a good idea to grant many permissions to a single app.
You are advised to use the excellent, open source [DAVx⁵](https://f-droid.org/packages/at.bitfire.davdroid/) app to synchronize/manage your calendars/contacts.
Most providers support exporting your contacts. Please [see here](https://support.google.com/contacts/answer/1069522) about how you can import contacts if synchronizing is not possible.
Displaying strange characters is almost always caused by specifying no or an invalid character encoding by the sending software. FairEmail will assume [ISO 8859-1](https://en.wikipedia.org/wiki/ISO/IEC_8859-1) when no character set or when [US-ASCII](https://en.wikipedia.org/wiki/ASCII) was specified. Other than that there is no way to reliably determine the correct character encoding automatically, so this cannot be fixed by FairEmail. The right action is to complain to the sender.
To store draft messages a drafts folder is required. In most cases FairEmail will automatically select the drafts folders on adding an account based on [the attributes](https://www.iana.org/assignments/imap-mailbox-name-attributes/imap-mailbox-name-attributes.xhtml) the email server sends. However, some email servers are not configured properly and do not send these attributes. In this case FairEmail tries to identify the drafts folder by name, but this might fail if the drafts folder has an unusual name or is not present at all.
You can fix this problem by manually selecting the drafts folder in the account settings (Settings, tap Manual setup and more options, tap Accounts, tap account, at the bottom). If there is no drafts folder at all, you can create a drafts folder by tapping on the '+' button in the folder list of the account (tap on the account name in the navigation menu).
Some providers, like Gmail, allow enabling/disabling IMAP for individual folders. So, if a folder is not visible, you might need to enable IMAP for the folder.
That said, FairEmail is able to properly handle sent messages in the inbox. FairEmail will mark outgoing messages with a sent messages icon for example.
The best solution would be to enable showing the sent folder in the unified inbox by long pressing the sent folder in the folder list and enabling *Show in unified inbox*. This way all messages can stay where they belong, while allowing to see both incoming and outgoing messages at one place.
If this is not an option, you can [create a rule](#user-content-faq71) to automatically move sent messages to the inbox or set a default CC/BCC address in the advanced identity settings to send yourself a copy.
[POP3](https://en.wikipedia.org/wiki/Post_Office_Protocol) is a very limited protocol. Basically only messages can be downloaded and deleted from the inbox. It is not even possible to mark a message read.
Note that you can hide messages and search for hidden messages, which is similar to a local trash folder, without suggesting that trashed messages can be restored, while this is actually not possible.
Version 1.1082 added a local trash folder. Note that trashing a message will permanently remove it from the server and that trashed messages cannot be restored to the server anymore.
This requires a compatible audio recorder app to be installed. In particular [this common intent](https://developer.android.com/reference/android/provider/MediaStore.Audio.Media.html#RECORD_SOUND_ACTION) needs to be supported.
* Enable *Separate notifications* in the advanced account settings (Settings, tap Manual setup and more options, tap Accounts, tap account, tap Advanced)
* Long press the account in the account list (Settings, tap Manual setup and more options, tap Accounts) and select *Edit notification channel* to change the notification sound
Sometimes the server received date/time is incorrect, mostly because messages were incorrectly imported from another server and sometimes due to a bug in the email server.
In these rare cases, it is possible to let FairEmail use either the date/time from the *Date* header (sent time) or from the *Received* header as a workaround. This can be changed in the advanced account settings: Settings, tap Manual setup and more options, tap Accounts, tap account, tap Advanced.
This will not change the time of already synchronized messages. To solve this, long press the folder(s) in the folder list and select *Delete local messages* and *Synchronize now*.
There is **only support** on the latest Play store version, the latest GitHub release and the F-Droid build, but **only if** the version number of the F-Droid build is the same as the version number of the latest GitHub release.
The F-Droid version is built from the same source code, but signed differently. This means that all features are available in the F-Droid version too, except for using the Gmail quick setup wizard because Google approved (and allows) one app signature only. For all other email providers, OAuth access is only available in Play Store versions and Github releases, as the email providers only permit the use of OAuth for official builds.
Note that you'll need to uninstall the F-Droid build first before you can install a GitHub release because Android refuses to install the same app with a different signature for security reasons.
The unread message count widget shows the number of unread messages either for all accounts or for a selected account, but only for the folders for which new message notifications are enabled.
Cancelling calendar invites (removing calendar events) requires write calendar permission, which will result in effectively granting permission to read and write *all* calendar events of *all* calendars.
Given the goal of FairEmail, privacy and security, and given that it is easy to remove a calendar event manually, it is not a good idea to request this permission for just this reason.
Inserting new calendar events can be done without permissions with special [intents](https://developer.android.com/guide/topics/providers/calendar-provider.html#intents). Unfortunately, there exists no intent to delete existing calendar events.
An email client is meant to read and write messages, not to backup and restore messages. Note that breaking or losing your device, means losing your messages!
If you want to import an mbox file to an existing email account, you can use Thunderbird on a desktop computer and the [ImportExportTools](https://addons.thunderbird.net/nl/thunderbird/addon/importexporttools/) add-on.
~~Besides that a [favicon](https://en.wikipedia.org/wiki/Favicon) might be shared by many email addresses with the same domain name~~ ~~and therefore is not directly related to an email address, favicons can be used to track you.~~
A *winmail.dat* file is sent by an incorrectly configured Outlook client. It is a Microsoft specific file format ([TNEF](https://en.wikipedia.org/wiki/Transport_Neutral_Encapsulation_Format)) containing a message and possibly attachments.
If the wizard ends with *AUTHENTICATE failed*, IMAP and/or SMTP might be disabled for the account. In this case you should ask the administrator to enable IMAP and SMTP. The procedure is documented [here](https://docs.microsoft.com/en-in/exchange/troubleshoot/configure-mailboxes/pop3-imap-owa-activesync-office-365).
If you've enabled *security defaults* in your organization, you might need to enable the SMTP AUTH protocol. Please [see here](https://docs.microsoft.com/en-us/exchange/clients-and-mobile-in-exchange-online/authenticated-client-smtp-submission) about how to.
To record voice notes, etc, the audio recorder needs to support [MediaStore.Audio.Media.RECORD_SOUND_ACTION](https://developer.android.com/reference/android/provider/MediaStore.Audio.Media#RECORD_SOUND_ACTION). Oddly, most audio recorders seem not to support this standard Android action.
Tracking images will not be recognized when the domain is classified as '*Content*', see [here](https://disconnect.me/trackerprotection#trackers-we-dont-block) for more information.
Updating once a week will probably be sufficient, please see [here](https://github.com/disconnectme/disconnect-tracking-protection/commits/master) for recent lists changes.
Permanent deletion means that messages will *irreversibly* be lost, and to prevent this from happening accidentally, this always needs to be confirmed. Even with a confirmation, some very angry people who lost some of their messages through their own fault contacted me, which was a rather unpleasant experience :-(
Advanced: the IMAP delete flag in combination with the EXPUNGE command is not supportable because both email servers and not all people can handle this, risking unexpected loss of messages. A complicating factor is that not all email servers support [UID EXPUNGE](https://tools.ietf.org/html/rfc4315).
If I could, I would add a setting to select the primary and accent color right away, but unfortunately Android themes are fixed, see for example [here](https://stackoverflow.com/a/26511725/1794097), so this is not possible.
Yes, [IMAP NOTIFY](https://tools.ietf.org/html/rfc5465) has been supported since version 1.1413.
IMAP NOTIFY support means that notifications for added, changed or deleted messages of all *subscribed* folders will be requested and if a notification is received for a subscribed folder, that the folder will be synchronized. Synchronization for subscribed folders can therefore be disable, saving folder connections to the email server.
**Important**: push messages (=always sync) for the inbox and subscription management (receive settings) need to be enabled.
**Important**: most email servers do not support this! You can check the log via the navigation menu if an email server supports the NOTIFY capability.
Message classification will attempt to automatically group emails into classes, based on their contents, using [Bayesian statistics](https://en.wikipedia.org/wiki/Bayesian_statistics). In the context of FairEmail, a folder is a class. So, for example, the inbox, the spam folder, a 'marketing' folder, etc, etc.
You can enable message classification in the miscellaneous settings. This will enable 'learning' mode only. The classifier will 'learn' from new messages in the inbox and spam folder by default. The folder property *Classify new messages in this folder* will enable or disable 'learning' mode for a folder. You can clear local messages (long press a folder in the folder list of an account) and synchronize the messages again to classify existing messages.
Each folder has an option *Automatically move classified messages to this folder* ('auto classification' for short). When this is turned on, new messages in other folders which the classifier thinks belong to that folder will be automatically moved.
The option *Use local spam filter* in the report spam dialog will turn on message classification in the miscellaneous settings and auto classification for the spam folder. Please understand that this is not a replacement for the spam filter of the email server and can result in [false positives and false negatives](https://en.wikipedia.org/wiki/False_positives_and_false_negatives). See also [this FAQ](#user-content-faq92).
A practical example: suppose there is a folder 'marketing' and auto message classification is enabled for this folder. Each time you move a message into this folder you'll train FairEmail that similar messages belong in this folder. Each time you move a message out of this folder you'll train FairEmail that similar messages do not belong in this folder. After moving some messages into the 'marketing' folder, FairEmail will start moving similar messages automatically into this folder. Or, the other way around, after moving some messages out of the 'marketing' folder, FairEmail will stop moving similar messages automatically into this folder. This will work best with messages with similar content (email addresses, subject and message text).
Classification should be considered as a best guess - it might be a wrong guess, or the classifier might not be confident enough to make any guess. If the classifier is unsure, it will simply leave an email where it is.
The message classifier calculates the probability a message belongs in a folder (class). There are two options in the miscellaneous settings which control if a message will be automatically moved into a folder, provided that auto classification is enabled for the folder:
* *Minimum class difference*: a message will only be moved when the difference in confidence between one class and the next most likely class is greater than this value (default 50 %)
Both conditions must be satisfied before a message will be moved.
Unfortunately, Android [does not support](https://stackoverflow.com/a/26511725/1794097) dynamic themes, which means all themes need [to be predefined](https://github.com/M66B/FairEmail/blob/master/app/src/main/res/values/styles.xml).
FairEmail is supported on smartphones, tablets and ChromeOS only.
Only the latest Play store version and latest GitHub release are supported. The F-Droid build is supported only if the version number is the same as the version number of the latest GitHub release. This also means that downgrading is not supported.
There is no support on things that are not directly related to FairEmail.
There is no support on building and developing things by yourself.