diff --git a/src/DownKyi/ViewModels/DownloadManager/ViewDownloadFinishedViewModel.cs b/src/DownKyi/ViewModels/DownloadManager/ViewDownloadFinishedViewModel.cs
index 68d520c..6ec73b7 100644
--- a/src/DownKyi/ViewModels/DownloadManager/ViewDownloadFinishedViewModel.cs
+++ b/src/DownKyi/ViewModels/DownloadManager/ViewDownloadFinishedViewModel.cs
@@ -140,7 +140,8 @@ namespace DownKyi.ViewModels.DownloadManager
             {
                 await Task.Run(() =>
                 {
-                    foreach (var item in DownloadedList)
+                    List<DownloadedItem> list = DownloadedList.ToList();
+                    foreach (var item in list)
                     {
                         if (item != null && item.DialogService == null)
                         {
diff --git a/src/DownKyi/ViewModels/DownloadManager/ViewDownloadingViewModel.cs b/src/DownKyi/ViewModels/DownloadManager/ViewDownloadingViewModel.cs
index 913f57c..7d2e826 100644
--- a/src/DownKyi/ViewModels/DownloadManager/ViewDownloadingViewModel.cs
+++ b/src/DownKyi/ViewModels/DownloadManager/ViewDownloadingViewModel.cs
@@ -178,7 +178,8 @@ namespace DownKyi.ViewModels.DownloadManager
             {
                 await Task.Run(() =>
                 {
-                    foreach (var item in DownloadingList)
+                    List<DownloadingItem> list = DownloadingList.ToList();
+                    foreach (var item in list)
                     {
                         if (item != null && item.DialogService == null)
                         {