The application object is being shut down how to solve?

There is a method that works when a button is pressed. It uses the async await construction.

private async void OkButton(object sender,RoutedEventArgs e) { //какая-то логика. for (int i = 0; i < ListOfFiles.Length; i++) { //какая-то логика. Window window=new Window(); window.Show(); await sem.WaitAsync();//где sem это SemaphoreSlim для того ,чтобы цикл не продолжал открывать новое окно,пока не закроется старое. //какая-то логика. } } 

So when you close the MainWindow when the Window is open. Exception is thrown. The exception is the application. I tried to sign the method on the MainWindow.Closed event, which:

  private void window_Closed(object sender, EventArgs e) { window.Close(); App.Current.Shutdown(); } 

But it did not help, when debugging, it turned out that even after calling the App.Current.Shutdown (); method. The OkButton method continues to work and when creating a new window, as the application terminated, in the Window designer, when the InitializeCompponent () method is called, it is displayed This error. I also tried to initialize the following property in App.xaml, with the following value ShutdownMode = "OnExplicitShutdown", but this did not help. Of course I can create a boolean variable and if it is false, do not create it in the for loop of the window. But I would like to understand why this is happening, and how it can be adequately Yes. When using the method, without an async operator, everything is fine.

I bring Stack Trace from an exception. Where AskReplace.xaml is a window window that is created in a loop.

at System.Windows.Application. GetResourcePackage (Uri packageUri) \ Leva \ Work \ Informatika \ CSharp \ My OPENSOURCE projects \ MusicSorter \ MusicSorter \ AskReplace.xaml: line 1 at MusicSorter.AskReplace..ctor (String userFileToReplace, Button buttonToCancel) in D: \ Leva \ Work \ Informatika \ CSharp \ My OPENSOURCE projects \ MusicSorter \ MusicSorter \ AskReplace.xaml.cs: line 59 at MusicSorter.MainWindow.CopyFile (String from, String to) in D: \ Leva \ Work \ Informatika \ CSharp \ My OPENSOURCE projects \ MusicSorter \ MusicSorter \ MainWindow. xaml.cs: line 218 at MusicSorter.MainWindow.d__10.MoveNext () in D: \ Leva \ Work \ Informatika \ CSharp \ My OPENSOURCE projects \ MusicSorter \ MusicSorter \ MainWindow.xaml.cs: line 181