VAC Was Unable to Verify Your Game Session

It's probably a false positive so contact Steam to verify your session

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Key notes

  • Valve Anti-Cheat (VAC) is an anti-cheat system for online games commonly used in games such as Counter Strike: Global Offensive (CS:GO).
  • When you play a multi-player game with other players, some of them may be using cheats and hacks to get ahead of everyone.
  • Such cheats, however come at a cost because if detected, your Steam account can get banned.

If you’re a gamer, you can appreciate that the true beauty of playing a game, aside from the graphic settings, uninterrupted gameplay comes a close second. Well, a VAC cannot verify the integrity of your game session data error message while playing on Steam does exactly that.

It could be a false alarm, or you’re using cheat codes, and Steam has finally caught up with you. Whatever the case, we provide you with various ways to get out of this mess below.

Why is VAC unable to verify my game session?

It’s not uncommon for gamers to explore various ways to get ahead of some games by modifying game files or using cheat codes.

However, to ensure fairness, Steam works closely with VAC or Valve Anti Cheat to keep tabs on players who try these tricks. VAC is a background anti-cheat software that monitors the state of games and their players. 

If you’re caught using any software that could give you an unfair advantage, you may get the VAC cannot verify the integrity of your game session data message or, worse, get banned from the platform. However, this is not the only reason.

This may have happened because:

  • You’ve been hacked – If the game you’re playing has been hacked, VAC will be unable to verify your game session, and you may receive a notice when trying to connect.
  • Outdated game – If your game client is not up-to-date with the latest security standards, you may not be eligible to play.
  • Game files modification – If you have changed some files in your copy of the game that Valve did not authorize, you may get the VAC was unable to verify your game session error.
  • Virus infection – Your computer may have been compromised by a virus or spyware, causing your game sessions to be flagged as cheating.
  • Using an unauthorized server – Steam explicitly prohibits using other servers, but some players use VPNs to access blocked sites or connect to other servers.
  • False positive – It is also possible for the VAC software to make a fake positive. These software are man-made, and sometimes, they, too, make mistakes.
  • Unsupported operating system – The latest version of VAC supports all modern versions of Windows, so if you’re seeing this message, it’s possible you’re on an unsupported platform.

How do I fix VAC authentication error?

Try the following basic checks first:

1. Disable your antivirus temporarily 

  1. Hit the Start menu icon, type Windows Security in the search bar, and click Open.
  2. Click on Firewall & network protection, then select Public network.league of legends black screen after champion select
  3. Locate Microsoft Defender Firewall and toggle the off button.turning off Microsoft Defender Firewall Windows

2. Disable VPN 

  1. Press the Windows key and select Settings.settings windows 11
  2. Next, select Network & internet and click on VPN in the right-side menu.
  3. Select the VPN connection you want to disable, click on the drop-down and select Remove.remove VPN

3. Scan for viruses

  1. Press the Windows key, search Windows Security, and click Open.
  2. Select Virus & threat protection.
  3. Next, press Quick scan under Current threats.
  4. If you don’t find any threats, proceed to perform a full scan by clicking on Scan options just below Quick scan.Scan options
  5. Click on Full scan, then Scan now to perform a deep scan of your PC.Full Scan Scan Now
  6. Wait for the process to finish and restart your system.

Sometimes, Windows Defender won’t detect and erase all of the digital threats, and for that, we suggest trying a reliable antivirus solution.

ESET HOME Security Essential, for instance, has high threat detection scores and advanced antivirus technology that will help you delete any trace of cyber threats and prevent them from affecting your PC system in the future.

⇒ Get ESET HOME Security Essential

4. Verify the integrity of the game files

  1. Hit the Windows key, type Steam, then open the desktop client.open steam from search box
  2. Click on Library.
  3. Right-click on the problematic game and select Properties.steam game properties
  4. Under Properties, click on the Local Files tab.
  5. Here, click on Verify integrity of game files.steam Verify Integrity of Game Files

CS:GO seems to be the game experiencing the VAC was unable to verify your game session issue, so ensure you downloaded it from Steam.

5. Repair the Steam Library folder

  1. Hit the Windows key, type Steam, then open the first result.open steam from search box
  2. From the top-left corner of the window, click on Steam.
  3. Go to Settings.navigate to settings menu
  4. Now, click on the Downloads tab.go to downloads
  5. In the right pane, click on Steam Library Folder.
  6. Right-click on the folder that is giving the error and select Repair Folder.
  7. Steam will run the troubleshooter and fix any problem with the folder.

If nothing works, you may have to reinstall the problematic games and see if the error persists. Still, there are an array of unorthodox solutions that some users claim helped resolve the VAC was unable to verify your game session issue.

For instance, a handful of users say changing their profile pictures and usernames resolved this issue. While there’s no correlation between the two, it certainly won’t hurt to try it out, especially if all the above have proved futile.

If you’re not adventurous, you can get in touch with Steam support and explain your issue.

While you’re still here, check out what to do when Steam fails to recognize your installed game.

That brings us to the end of this article, but we’re keen to hear any other solutions that may have worked for you, so get interactive in the comment section.

More about the topics: Steam games