So, i have a problem with Alien Swarm. When i start it, the “Preparing to launch Alien Swarm” window comes and then disappears. The swarm.exe process is running for a couple of seconds, and then it goes away. All my other Steam games lauch fine (Portal, Garry’s Mod). Reinstalling takes so much time, so i’d rather try to find a fix first, and see if i can get it to work 
Anyone knows of something?
Verify the game’s cache contents, first of all.
If that fails, try closing steam, removing the ‘bin’ folder from the alien swarm directory, and then restarting steam.
If all of that fails, restart your computer and try again, before reinstalling.
If all else fails, call Valve a fag and ask for a refund.
You do realize that Alien Swarm is a free game, right? You want him to insult Valve and then tell them to give him money for free content?
It was a joke.
RabidMonkey, verifying worked! Thanks! I totally forgot that function 
Is it cold outside? Sometimes the game engine has ignition problems when it’s really cold out. Try clicking the shortcut harder.
Pouring hot liquid on the icon may help as well.
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