I just purchased and downloaded Dishonored on Steam. When I tried to launch the game, it ran the first time setup and then crashed with a long error message. I'd post a link to a screenshot of the message (which I couldn't copy/paste) but for some reason I'm not allowed. Really helpful. Basically it says Dishonored.exe and a few dlls were not found.

I tried using Steam to verify file integrity but the same thing happened when I tried to launch. The files which the error message says are not there are all there when I check manually in windows explorer. Launching from Explorer instead of Steam gives the same error.

System specs:
Intel i7-3770 CPU @ 3.50 GHhz
16 GB RAM
AMD Radeon HD 7950
Windows 7
DX 11