The BACKEND REJECTED THE CHALLENGE RESPONSE error OR being unable to connect to other players, craft or open Spoils of War indicates that you may be playing on the 'Modded' realm. If this is not applicable to you, it is issue with our anti-cheat service, Easy Anti-Cheat.

Switch Realms

The most common cause of this error is when a player has the Modded realm selected, as opposed to the Official realm.

Your realm can be changed within the Vermintide 2 launcher, using the checkboxes on the right-hand side of the 'Play' button.

Remove the Easy Anti-Cheat Certificates & Install/Repair Easy Anti-Cheat

1. Firstly, delete the EAC Certificates directory:

   1. Navigate to: C:\Program Files (x86)\Steam\steamapps\common\Warhammer Vermintide 2\EasyAntiCheat
   2. Delete the ‘Certificates’ directory

   Next, uninstall and reinstall EAC_EOS using Powershell commands:

   1. Go to the Vermintide 2 Easy Anti-Cheat EOS directory:
      C:\Program Files\Steam\steamapps\common\Warhammer Vermintide 2\installers\EasyAntiCheatEOS
   2. Shift + Right-click in the folder and select ‘Run Powershell window here’
   3. Paste the following command:

      .\EasyAntiCheat_EOS_Setup.exe uninstall e020ce70c5b74c38805c6f3f910bac22

   4. Press enter
   5. Then paste the followng command:

      .\EasyAntiCheat_EOS_Setup.exe install e020ce70c5b74c38805c6f3f910bac22

   6. Press enter

   Lastly, Verify Integrity of Game Files:

   1. [PC] How to 'Verify Integrity of Game Files' via Steam

Verify Integrity of Game Files

The 'Verify Integrity of Game Files' option is accessible via the Steam client and will ensure the installation is complete. 

1. Right-click Vermintide 2 in your Steam library sidebar
2. Select 'Properties'
3. Select the 'Local Files' tab
4. Select the 'Verify Integrity of Game Files' button
5. When complete, close and reopen Steam