private void _server_ScreenShareRequested(object sender, ScreenShareRequestedEventArgs e) { Dispatcher.Invoke(async() => { var result = MessageBox.Show ( Application.Current.MainWindow, $"Screen share requested by: '{e.RequestorId}'. Do you Accept it?", "Share screen", MessageBoxButton.YesNo, MessageBoxImage.Question ); if (result == MessageBoxResult.Yes) { await _server.AcceptScreenShare(e.RequestorId); } }); }