How to Fix CS:GO and CS2 Error "VAC Was Unable To Verify Your Game Session"?

Both CS:GO and CS2 are extremely successful iterations of our beloved franchise, but just like with any other game, they are not without a few flaws here and there. From time to time, players encounter the extremely frustrating “VAC was unable to verify your game session” message, randomly popping up and denying access to official servers. Fortunately, there are a few ways of dealing with this issue, given that you’re not using cheats or third-party software. In this article, we’ll explain what causes this error and how to fix it step-by-step.   

What is VAC in CS:GO and CS2?

VAC stands for Valve Anti-Cheat and it is a system that is used to detect cheats installed on players’ personal computers. VAC is necessary to ensure fair play in competitive multiplayer games, so that no player has unfair advantage over the others. Valve can track down and impose bans on players running cheats in multiplayer games such as Counter-Strike 2 and Dota 2.

 What Does It Means “VAC unable to verify your game session” in CS2

You may encounter the “VAC unable to verify your game session” error when VAC cannot confirm that your game is not modified or altered. Don’t worry just yet, it doesn’t mean that you’re running cheats on your computer, it can happen to anybody. This error may be caused by many things, including corrupted game files, third-party software interference, issues with your PC/operating system or Steam issues. There was a massive failure on the Steam side a few months ago when many users encountered this error at the same time. If VAC was unable to verify the game session on your computer, there’s probably an easy fix that might help you get back to top-fragging in no time. 

How to Fix Error “VAC Was Unable To Verify Your Game Session” in CS:GO and CS2

Now, let’s get to the meat and potatoes. There are a few ways of dealing with this issue, so let’s start with the simplest one:

1. As weird as it sounds, some players get rid of this issue by simply changing the nickname and the profile picture in Steam

• Launch Steam, click your profile

• Click ‘Edit Profile’ and then proceed to change your nickname and your profile pic

2. If this didn’t work, then you may want to verify the integrity of game files

• Launch Steam, then proceed to your Library

• Find CS2 in the list and right click on it

• Proceed to Properties, then to Installed Files

• Click the ‘Verify integrity of game files’ button

• Wait until the process is complete, then restart the game

3. Some players reported that this small fix helped them get rid of this error

• Launch CS2, then start a game with bots

• Leave the game and restart Steam

• You’re good to go!

4. There’s also a strong possibility that your firewall is clashing with CS2

• Once you’ve completed the verification of game files, open the search bar in Windows

• Type and open ‘Firewall & Network Protection’

• Click ‘Allow an app through firewall’

• Click Change Settings then find CS2/CS:GO in the list

• Click on both ticks near the CS2 line

The ‘VAC is unable to verify game session’ error is rarely related to the actual use of cheats. However, it is also important to remember that running cheats on your PC may result in VAC ban, even if you’re doing it as a joke with your friends on a private server. Once VAC detects cheats, your Steam acc might face a banhammer that will prevent you from playing on protected servers and permanently leave a mark on your account, considerably lowering the amount of features and potential rewards you could get in the future.

VAC Error FAQ

Does the "VAC was unable to verify your game session" error mean I'm banned?

No. This error simply means VAC couldn't confirm your game files are unmodified — it is not a ban and usually isn't related to cheating at all. It's commonly triggered by corrupted files, third-party software, firewall conflicts or Steam-side hiccups, and it's typically fixed within a few minutes. 

Does verifying game files delete my skins or settings?

No. Verifying the integrity of game files only checks your local install and re-downloads any missing or corrupted files. Your inventory lives on your Steam account, not on your PC, so your skins are safe, and your in-game settings and configs stay intact through the process. 

Can I get a VAC ban for cheating on a private server?

Yes — running cheats can trigger a VAC ban even if you're only messing around with friends. A VAC ban is permanent, marks your account for good and blocks you from VAC-protected servers, so it's never worth the risk regardless of the setting.