Cant Play MW2.

Well After my long day of Hacking.. i got disconnected from steam. then when i tried clicking on the game it said, Steam has Failed to Sync Cod Modern Warfare 2, then i go into the game and when i press play it says : Steam Must be in Online mode in order for u to play. Can any1 explain why this is happening?

do you run hacks or other programs which can conflict mw2?
and nice avatar btw

same thing just happened to me... i restarted my computer... dumped my steam files and let it re update. It works fine now, and the hacks still work.