WPF Application still runs in background after closing
What is your shutdown mode? If it's explicit, then it's because you're not explicitly shutting down. If it's main window, it's because you've not assigned the main window to Application.MainWindow.
Write this code on application closing button:
Application.Current.Shutdown()
alternatively, add this to your App.cs
public App() { ShutdownMode = ShutdownMode.OnLastWindowClose; }