I just got Dead Money through Steam and after it downloaded and installed I was unable to launch Fallout: New Vegas. It keeps displaying a message that the Gamebryo Renderer failed to load, an unknown error prevented the Gamebryo Renderer from being created.

What can I do?

I am trying two things after this post - one is validating game files through Steam, as of now it says 1 file failed to validate, so it will reacquire that. If this doesn't work, I'm going to try restarting my PC and maybe deactive SLI (since I saw some posts across the internet that somehow linked ATI Crossfire with causing a similar error with Fallout 3)

Validating game files through steam did not work.

System specs:

Windows 7 Home Premium 64-bit

Core 2 Duo processor
4 GB RAM
dual Nvidia GeForce 8800 GTX combined in SLI

Restarting my computer DID WORK!

So at least in my case, restarting the PC is enough of a solution.