Null reference pointer was passed to the stub when not debugging with IE

Question

In VS2012, my web project debugs fine like always. I use IIS Express. Today, I installed VS 2013 and when I press F5 to debug, I get

Answer 1

I've just had the opposite problem, which the last post solved for me!

I've upgraded a Silverlight project from VS2010 to VS2013 (and I can confirm that if you've used a Domain Service you're in trouble; despite what Microsoft say, the project would NOT compile under 2013 and gave an error for EVERY edmx datatype, stored procedure etc!).

When I finally got it compiled after a day's slog (and no it's not backwards compatible, this is a 1-way upgrade), it ran, but behaved slightly differently. So I put in some breakpoints which it proceeded to completely ignore.

The Silverlight debugger needs to be checked but wasn't. I assumed it was part of the vbproj file? Have had no problems with the IE settings.

Ade