hl2.exe error!

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Have you got the latest DirectX?

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Did you try reinstalling DirectX 9c?

Also, what are computer specs?

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Only thing that I that I can that is wrong is that there isn’t loads of RAM, but there is enough to run those games.

See what happens once you reinstalled.

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I’m sure you do (since gmod doesn’t come without one) but make sure you have a source game installed.
If you have the Orange Box, download all the games - although it shouldn’t be essential to run gmod, half-life 2: episode 2 is used by many maps, at the least.
If you’ve installed any addons, remove them. Just try running gmod without any addons installed. If you do want any addons, however, just get PHX3, wiremod SVN…but not stargate unless you have a good reason. It messes many things up.
try installing CCleaner (google it) as well. You said you madesure it was a clean uninstall. Well, after doing that but NOT INSTALLING AGAIN, run ccleaner and the registry cleaner it comes with, then run the disk cleaner and defragmenter that come with the PC just to be safe. THEN reinstall.
Sorry if I’m no help…that’s the best I got. Good luck

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Just to be safe, if you bought them, download ALL the orange box games: Half-Life 2, Episodes 1 and 2, TF2, Portal, and even get the free HL2: Lost Coast. Make sure they’re all checked if you can make it to the main menu and go into Gmod Options.

did you try going into this file?

C://Program Files/Steam/Steamapps/user-name here
and deleting your Garry’s mod, tf2, or portal file then re downloading it?

oh wait… im dumb you said you did lol

oh ok so hum… just delete your steam folder, then download it again, if you did that then you may have a hl2.exe virus. in that case then it runs off of the program you were using, and may have made a new file some where else on your computer. i would suggest doing a computer scan. and if youv’e made any new downloads off of like garrysmod.org then delete those files as well

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dam… sorry that i couldn’t help, maybe its just your graffics card

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