Happend today.
Today my Macbook shut down automaticly.
After restard and opening Steam. Steam screen stays completly black. Only thing i can open is an advertisement.
Not possible to start Cod4 : (

Even reinstalled Steam. Nothing changed.
I hope i deleted with this not my profile.

Someone else has this problem?

Best wishes
Masartus

* I just noticed i can open the cod4 programm parallel and the game is running.
I thought i can only open it via Steam.hmmm

Masa try the solution for "steam" posted just a after this one. but for mac change the path to:

/Users/USERNAME/Library/Application Support/Call of Duty 4

all that money  time too buy