In your WPF application’s Exit command handler, be wary of calling App.Current.Shutdown unless you want to bypass the normal ‘Close’ process. It can result in your override of OnClosing to NOT be called, and your closing-event handlers don’t get called either.
If you override the Onclosing method, don’t forget to call the base class OnClosing!
Oh – if your WindowSettings functionality is not working, check for this mistake.
Of course I’ve never done that myself. Oh no. Neeeever.