XAMLParseException driving me CRAZY!

Question

THIS XAMLParseException IS DRIVING ME CRAZY!! I am using .NET 3.5 in Visual Studio 1020 This is my xaml:

Answer 1

I know that this is an old question but hopefully this will help someone.

I had a property of the main window that was a Business Object... so when the window initialized, the Business Object attempted to initialize... great, but the Data access layer had not been setup, therefore it threw an error...

So c# called that an XML parse error because it happened so early... really it was thrown in code.