is very simple to fix it!!
- close steam
- make new folder in C://program files with "clean" name like STEAM(be careful no like steam! or steam1 just steam)
- copy all steam and call of duty files from old folder in new folder!
- open steam from new folder and go Game library!
- right click on game->properties->Local files-> verify intercity of game...
- wait for a small download
And now can enjoy the Game!!