SolvedPreparing to launch failure

So i was going to log on MW3 today and then as usual it says preparing to launch call of duty modern warfare three multi-player but it has been there for a while, so i canceled the launch and launched another game, it worked fine it was weird so i logged in and out of steam and it had trouble signing in saying Something that has to do with my connection but a few minutes later i got to sign in. When i signed in the same error occured, now i'm not sure if this has happened to many people but to be on the safe side i'm going to re-install

Happens sometimes, i just kill the process and start steam normally. Works every time

If it isn't working still try verifying game cache, might work. Right click mw3 in steam then go to properties>local files tab>verify integrity of game cache.