If you’re trying out Visual Studio 2010, and you try to open source code file with the “Solution Explorer”, you might encounter a nice exception like this one :

---------------------------
Microsoft Visual Studio
---------------------------
Object reference not set to an instance of an object.
---------------------------
OK
---------------------------

That could not be more vague..

After a small debugger analysis, it seems like VS2010 does not support TrueType fonts, but does not prevent their selection in the font selection dialog.

I was using “Proggy Opti Small” with VS2008, which is not TrueType... So to be able to open you source files, use a font like Consolas, and restart VS2010.

A bug report exists on Connect.