So I'm trying to launch Left 4 Dead 2 from Steam while I'm logged in, the game starts up, shows the intro movie and exits the game and tells me that Steam is not running and that I have to start Steam to play the game
 
So, I don't play alot of Steam games, what the hell is going on?

Is this happening with Left 4 Dead 2 only or with all your Steam games?

" Is this happening with Left 4 Dead 2 only or with all your Steam games? "

" @FlamingHobo said:

" Is this happening with Left 4 Dead 2 only or with all your Steam games? "

I launched Alien Swarm and the same thing happened there "

Are you signed into Steam Friends? If not, games like L4D2 won't work.

" Are you signed into Steam Friends? If not, games like L4D2 won't work. "

" @FlamingHobo said:

" Is this happening with Left 4 Dead 2 only or with all your Steam games? "

I launched Alien Swarm and the same thing happened there "

" @FlamingHobo: Thanks, restarting Steam worked "