Source SDK won't launch?

[WolfKit]

So, Hammer crashed while compiling after finding a leak, so I closed it. Now, I can't launch Source SDK. I tried verifying local files for both SDK and TF2, but it didn't help. Is anyone else having troubles?
EDIT: Reinstalled SDK, no joy.
EDIT: Restarted Steam, it's working now.

 

[Crash]

Sometimes VRAD or VVIS gets stuck open and doesn't allow hammer to rerun. Either a restart of steam or manually stopping those processes usually allows hammer to work again.