A little weirdness with Visual Studio 2012 – the Source Control Window disappeared and nothing seemed to bring it back. I could open a solution from the Recent list, and open a file from the Solution, but still no Source Control Window would launch or display. And View -> Other Windows -> Source Control Window did nothing.
All until a colleague pointed out that, if you watched closely, it seemed like the window was loading, just not visible. So we tried Window > Reset Window Layout and all was well.
Drove me crazy for 15 minutes – and the simplest solution turned out the right one.