What UI frameworks do you use? Some .Net UI Frameworks indeed provide you some “Load” events, but also some happen to SILENCE all exceptions that happen during your even-handlers, “to provide better UI Experience to the end user”.
You can check easily if any exceptions are thrown in the OUTPUT panel under debugger. If you see any “First chance exception” – then here you have it, your UI Framework is “quiet one”.
Add try-catch, or add application.unhandledexception eventhandler, and just try to bear with your quiet UI..
If I recall correctly, the WPF liked to silently skip exceptions, while WinForms tended to crash instantly. But I may be wrong here.