I have written a C# Windows Forms application, not a service (it is only used when the user is logged in and has a graphical user interface) that has a background thread running in an infinite loop. When I try shutting down Windows (7) however, it tells me the program is preventing it from shutting down or logging off and asks me whether I want to force a shutdown. Now, is there any possibility for my program to become aware (get a handler) of Windows trying to quit it or to log off? So, what I need is to make the application realize when Windows tries to quit. Thanks in advance.