Small improvements

app/src/main/java/eu/faircode/email/ApplicationEx.java

@@ -57,6 +57,7 @@ import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.FileWriter;
 import java.io.IOException;
+import java.net.SocketException;
 import java.net.SocketTimeoutException;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -191,6 +192,7 @@ public class ApplicationEx extends Application {
                     if (ex instanceof MessagingException &&
                             (ex.getCause() instanceof IOException ||
                                     ex.getCause() instanceof ConnectionException ||
+                                    ex.getCause() instanceof SocketException ||
                                     ex.getCause() instanceof SocketTimeoutException ||
                                     ex.getCause() instanceof ProtocolException))
                         return false;

app/src/main/java/eu/faircode/email/Core.java

@@ -753,7 +753,7 @@ class Core {
         if (!found) {
             db.attachment().setError(local.id, "Attachment not found");
             if (!EntityFolder.DRAFTS.equals(folder.type))
-                throw new IllegalArgumentException("Attachment not found");
+                throw new IllegalArgumentException("Attachment not found: " + local);
         }
 
         updateMessageSize(context, message.id);