pls help missing file from Call of Duty MW3

Hi, i try to play Call of Duty MW3 at survival mode but i have error message that

file : so_survival_mp_mogadishu.ff

is missing can any one upload it to me pls ???!!!

Steam should download it, if you check your gamefiles...

Steam-> Right Click on the game -> Properties -> Local Files -> Verify Integrity of Game Cache...

Then it will check all your files for damaged or missing files and will download them.