Portal 2 first starts great, second start fails?

[KomradDan]

When I first got Portal 2 it started up just fine. Wake up the next day and tried to start it up but it acts like it's about to start almost playing the Valve into but then just crashes. No error report or anything. I tried verifying the game, didn't work. Restarting steam, didn't work. Restarting computer, didn't work. So I decided maybe I just need to reinstall the whole game so I tried that. It starts out great but the second and every following startup it still crashes just when the black screen pops up with no error report. I don't know why the first time I start it up is fine and every time after fails. Any tips and help would be very appreciated. I don't know if this has already been mentioned in a previous discussion and I'm kind of new to steam so if this has been brought up before just post the link and I will delete this. Thanks.

[qazwax01]

My Portal 2 starts excellent, every time.

[Wasabi_Thumbs]

THIS WORKS WITH ANY PORTAL 2 PROBLEM!

(Except Screen resolution problems)
I tried it myself!

Go to your Steam Folder, delete appcache, go to the SteamApps Folder, delete the Portal 2 folder manually, reboot steam, right click Portal 2 in your library and press Delete Local Content, then press Install. This really works! I tried it myself! The valve animation went, then I saw that picture of The Co-Op Robot P-Body jumping into a portal and then it crashed. The usual location of your steam folder would be
Windows 64 Bit = C:\Program Files (x86)\Steam
Windows 32 Bit = C:\Program Files\Steam
Mac 64 and 32 Bit = ~/Library/Application Support/Steam
Other Operating Systems = Don't Know.

[KomradDan]

Didn't work. I actually noticed that it happens after I get an error message about vrserver.exe has stopped working. I have no idea what that is or what VR stands for, but I think it's part of the problem with portal 2.

[Perseus]

VR: Virtual Reality. The vrserver.exe is part of SteamVR. And Portal 2 is one of those programs with VR support. But some antivirus programs are blocking vrserver.exe. They believe it is a virus or malware. You should check if your antivirus program is also blocking it. That's probably why Portal 2 runs only once on your system after installation.

[KomradDan]

My antiviral software scanned the vrserver.exe and says there's nothing wrong with it. Also when Portal 2 crashes I don't get an error report or my antiviral software telling me there's something wrong so I don't think that's the problem. Maybe I'm just not seeing things correctly because I'm willing to admit that, while I'm determined to get Portal 2 working, I know that I don't know much of what I'm doing. So even baby steps you might offer would be appreciated.

[Perseus]

Okay, I'll tell you what to do. But can you first tell me your operating system and screen resolution? Or have you already solved your problem?

[KomradDan]

My operating system is Windows Vista and my screen resolution is 1980 x 1080. Sorry for late reply

[KomradDan]

I think I found the problem. It looks like it's being blocked by my Data Execution Prevention. I attempted to turn it off for vrserver.exe but the stupid thing said I absolutely can't disable DEP for it. It didn't ask for admin permission or anything, it just siad it CAN'T do it.

[Perseus]

But I can run Portal 2 on my Vista computer without any problem. What is the setting of DEP on your computer then? Right click on Computer (the computer icon at your desktop or on the name Computer in your Windows menu), choose Properties and then left click on 'Advanced system settings'. Click on Settings of Performance (the one at the top) and there you can check the DEP setting on your computer. The option at the top should be selected. But if you click on the option below you can tell the computer to make an exception for certain programs. Make that exception for your blocked program and check if it's still being blocked.
You can also check what would happen if you completely disable DEP on your computer. This can only be done with an administrator account. Left click in your left lower corner on your Windows icon and type cmd in the textbox above. Type the following command in the command line interface window:

bcdedit.exe /set {current} nx AlwaysOff

And reboot your computer. Now DEP should be fully turned off on your computer. You can turn DEP back on by typing:

bcdedit.exe /set {current} nx AlwaysOn

But DEP is for the protection for your computer and a program will become vunerable for attacks if DEP has been turned off for that program.

[KomradDan]

Well that's how I tried to turn off DEP for vrserver and I got the message saying I can't turn it off for it. "This program must run with Data Execution Prevention enabled. You cannot turn off DEP for this program." and I don't think I'm willing to just shut off the DEP completely.

[Perseus]

But it is only as a test, to see if Portal 2 would still have a problem after DEP has been disabled. After that test you could simply turn DEP on again.

[KomradDan]

Damn it it didn't work. Portal 2 crashed the same way even with DEP off. This doesn't make any sense.

[KomradDan]

Well I found something quite interesting and strange. I tried going to the actual exe file in "Program Files(x86)/Steam/SteamApps/common/Portal 2" and ran it from there but this time I did it while I was logged off from Steam, and the weirdest thing happened. It started up normally! I got through the entire Valve intro and I was so excited but once it showed the loading screen for Portal 2, it crashed right there. How come it lasted longer when I was logged off, but still crashes?