[SOLVED] Easy Anti-Cheat Error: Untrusted system file in Windows & Linux Proton

When launching multiplayer titles defended by Easy Anti-Cheat (EAC), the boot process halts with a popup warning: Easy Anti-Cheat - Untrusted system file (C:\...\file.dll). The anticheat kernel driver detected an unrecognized checksum or missing digital signature on the specified library and blocked execution to prevent memory injection attacks.

Step-by-Step Solution

Step 1: Audit the File Path Flagged in the EAC Modal

Examine the exact absolute path specified in the alert:

• If pointing to System32 or SysWOW64, an OS component has failed digital signature verification.
• If pointing to your game directory or screen recording tooling (OBS, RivaTuner, Overwolf, Discord), an external injection hook is triggering the heuristic filter.

Step 2: Disable Screen Overlays and Graphics Injection Tools

Completely terminate ambient utility programs prior to launching:

1. 1

   RivaTuner Statistics Server (RTSS):

   Lower application detection level to None or exclude the game executable.
2. 2

   ReShade:

   Remove custom dxgi.dll or d3d11.dll wrappers from the game folder.
3. 3

   Step 3

   Turn off Discord and NVIDIA GeForce Experience game overlays.

Step 3: Repair Easy Anti-Cheat Service or Steam Runtime

On Windows:

1. Navigate to the game's directory and enter the EasyAntiCheat subfolder.
2. Right-click EasyAntiCheat_Setup.exe and choose Run as Administrator.
3. Choose your game in the selector and click Repair Service.

On Linux / Steam Deck: Ensure the tool Proton EasyAntiCheat Runtime is downloaded and up to date in your Steam library.

Frequently Asked Questions

Why does EAC flag legitimate Windows libraries like crypt32.dll?

A corrupted Windows Update can break local certificate catalog validations. Fix with DISM /Online /Cleanup-Image /RestoreHealth followed by sfc /scannow.

Does Easy Anti-Cheat support Proton on Linux?

Yes, if the studio enabled Wine/Proton EAC support server-side and the Steam user has installed the Proton EasyAntiCheat Runtime.