Problem building projects in VS 2012

I’ve just installed VS 2012 for Desktop and Monogame, then I’ve created a new monogame project and tried to build It without change anything in It in order to see the blue screen and verify that everything works fine, but instead I’ve got this:

‘System.NullReferenceException’ occurred in MonoGame.Framework.dll

I’ve been searchin’ but I can’t find the reason of the exception

Could someone help me, please?

I understand some Visual C# and could help somewhat if I see the code…
Useless otherwise…
Also try just loading another file and spotting differences…
Not the most helpful…

I tried that too but it’s not working.
And as I said, there isn’t really any code, I’m trying to build the “original project” without any change in it.

I’m out of knowledge…
I’m just a student in a video game design class.
At least I tried.

I appreciate it. Thanks anyway
I’ll keep searching