Portal 2 Crashing Right after First Load Screen

[March]

So I had just finished getting all the single player achievements when my Portal 2 game crashed?? I turned off the computer after waiting about an hour. When I started it back up, it wouldn't get past the first loading screen right before the main menu. I've looked at some other people's discussions and they've told me that
1) Validate your Steam Files
2) Reinstall Portal 2
3) Maybe it's your computer

I've already tried reinstalling (and this is what made me lose about half of my achievements), but it still does nothing. My computer's fine, I have some other games much bigger than Portal 2 and it was fine before when I played it.

I don't know how to validate my steam files, and if that doesn't work, what else could I do?

[☭TSAR_]

Try running Steam in offline mode, that's oddly helped a lot of people. If that doesn't work, run it in winowed mode by going to launch options and typing -windowed. Do not reinstall the game, if you're trying to reovor files, then just validate your integrity of game cache. To do this, go to your Librarby, right click portal 2, click properties, then local files, then Validate Integrity Of Game Cache.

[March]

Ah, it worked! THANK YOU SO MUCH!!!!!!!

[☭TSAR_]

Originally posted by hanazaki462anime:

Ah, it worked! THANK YOU SO MUCH!!!!!!!

Glad to help

[Voice]

I still have this error :(

[Valstrath]

TF2 gives me an error, and i feel it is a problem related to this, and i also have this problem >_<

[Tsunami]

After I upgraded to Windows 8.1, this happened to me as well. (Post hoc ergo propter hoc.) Stereoscopic 3D was also turned on. Using the -windowed option fixed the crashing problem (thanks Smitty!), but I had to uninstall the Nvidia 3d modules to get rid of the 3d effect in Portal 2.