Completely unable to start up Garry's Mod or any Source Game?!

It’s been happening for a couple of months now. I reinstalled Garry’s Mod. I cleaned up my entire GMod file of addons. I formatted my hard drive and backed up my old GMod folder. I copied that folder and put it in /steam/steamapps/darkglados/garrysmod. And it’s still screwing up! And after that happens, absolutely no game that is called “hl2.exe” will start up. I look in my Task Manager and I see the process, but the game doesn’t start up. I mean, earlier, when I had my hard drive formatted but the old GMod folder not copied, it worked. But then when I copied it, same thing. Rebooting doesn’t do anything. Nor does cleaning up my GMod file AGAIN.

Please tell me anything that could possibly help me. I appreciate anything at this point.

Verify the integrity of the game cache

Right click Gmod
Click properties
Click local files
Click Verify integrity of game cache

Thanks a lot! I sure hope it works, though.

Nope, no luck. Do I have to restart Steam first or something?

Restart steam, or restart your PC.

Go to steamapps/yoursteamname/garrysmod

Inside that file rename the folder “garrysmod” to “garrysmodold” then run the game from steam

The hilighted folder is the one you should rename, just so you aren’t confused.

It will create a new folder for garrysmod

See if it launches then

I have this exact same problem, only it’s my HL2DM and GMod not starting up. I tried literally everything, even trying vanilla GMod. No luck. I formatted Windows, GMod works fine when I reinstall Steam, but after 2 or 3 startups the cursor shows the glowing ring for a few seconds and then just turns into a normal cursor.

Dude, what do you think I meant by cleaning my Garry’s Mod folder? That’s exactly what I did, but no luck.

I’m sorry for trying to help, most people don’t know that they should do that, and you didn’t say you’d done that you just said clean. I’ll stop trying to help just so I don’t piss you off further

Skidmarks, I can honestly say that I have also tried that multiple times. The thing is, I have to reformat my PC everytime and reinstall Steam to make GMod work, which it does for 2-3 startups then after that when I try to run it again, my cursor turns into a ring and just stops. “hl2.exe” is sitting in the Task Manager but it’s not even going fullscreen. And I checked, no error dumps in my GMod folder as well.