based on the MVVM Light 4 beta template I created a 7.5 app and just put a listbox on the mainpage. No other pages. I created a ResourceDictionary with some styles. In the designer, the mainpage shows nicely with some sample data.
But when I run the app, the simulator starts the app but stalls at the splashscreen (the default grey clock).
When I step through the UI I see nothing wrong, it goes through the whole initialisation as far as I can see.
How can I debug such as situation further?
Are you able to set and hit a break point at
Application_Launchingin App.xaml.cs? If not, try setting up a new MVVM Light 4 project and slowly add the existing pieces from your problem application to the new project (making sure it runs each time) until you hit your exception.