How to fix "VAC was unable to verify your game session" | CSGO | VAC

Easy guide about how to fix the "VAC was unable to verify your game session" error message with several alternative options to resolve the issue in Counter-Strike Global Offensive / CSGO.

What is VAC aka Valve Anti-Cheat?

Valve Anti-Cheat (VAC) is an anti-cheat software product developed by Valve as a component of the Steam platform, first released with Counter-Strike in 2002.

When the software detects a cheat on a player's system, it will ban them in the future, possibly days or weeks after the original detection. It may kick players from the game if it detects errors in their system's memory or hardware. No information such as date of detection or type of cheat detected is disclosed to the player. After the player is notified, access to online "VAC protected" servers of the game the player cheated in is permanently revoked and additional restrictions are applied to the player's Steam account.

Source: Wikipedia[en.wikipedia.org]

What does the error message mean?

"VAC was unable to verify your game session" means that VAC was unable to verify your game session because it detected a third-party program, a script that attempted to alter the game processing or any kind of tempering in your game files.

How do I fix it?

• Option 1: Run the game as administrator.
  1. To do that you need to find your csgo.exe file. The csgo.exe file is located either in C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\ or C:\Steam\steamapps\common\Counter-Strike Global Offensive.
  2. Open its propreties, click on the 'Compatability' tab and check the 'Run this program as administrator' checkbox.
  
  
• Option 2: Turn off your Anti-Virus & Windows Defender / Exclude CSGO from said programs.
  Sometimes AV programs and or Windows Defender interfere with the game which results in the error message. I suggest restarting your PC after doing so.
  
  
• Option 3: Verify integrity of game files.
  Right-click on CSGO in your library, select 'Properties' from the menu, select the 'Local Files' tab and then click on the 'Verify Integrity of game files' button. Wait for it to finish before opening CSGO again.
  
  
• Option 4: Repair Steam Service.
  1. In order to do so, you need to first exit Steam and open your Command Prompt (CMD) / Windows Powershell as Adminstrator. In order to do so, press on Windows Key + X and click on Command Prompt (Admin) / Windows Powershell (Admin).
  2. Once the window is open, paste the following and press enter: "C:\Program Files (x86)\Steam\bin\SteamService.exe" /repair
  3. Open Steam again and check if the issue has resolved.
  
  
• Option 5: Fresh Install of CSGO and or Steam.
  Hopefully you wouldn't need to do this, but if none of the above works, fresh install would fix the issue.

Summary

Thanks for visiting my guide and reading it through.
Hopefully one of the alternative options to resolve the issue helped you.
If the guide helped you, I would love if you could upvote and leave a comment.
If the guide hasn't helped you, please leave a comment explaining the issue you are facing and I'll do my best to try and help you resolve it as quick as I can, cheers.

Stay frosty, sKratchy.

[ManBearPig]

step one delete windows step 2 throw computer out the window.
10/10 guide would waste 3 hours again.

[전설의USP]

아니 뭐냐고 진짜

[Sean_T]

Ran into this problem today. I closed open programs one by one until the error went away. Riot Vanguard was the culprit.

[PHANTASY]

just play faceit, problem solved!

[aamin']

don't you dare uninstall you AV.

[RageKitten]

The fix isnt working for me either.... please help !

[TOPSHOTTA]

I literally tried all the solutions, I was having no problem until there was a windows update, tried reverting and it still is giving me a problem SMH

[ꓲ ꓯ ꓒ]

How should I do this repair in linux? I have uninstalled and deleted everything. Changed graphics drivers to all the other older version, closed every other program, rebootet like 20 times and still VAC is unable to verify my session. VAC that so rarely bans obvious cheaters makes but makes clean players unable to play bought games.