How to Fix “Anticheat Failed to Start” in Gray Zone Warfare

If Gray Zone Warfare shows “Game Couldn’t Be Started (0X00020004) — Reason: Anticheat failed to start,” begin by fully restarting Steam and verifying the game files. That verification is the most specific low-risk step reported for this exact message. If it does not help, MADFINGER’s official Easy Anti-Cheat repair and security-software guidance covers related errors, but neither is confirmed as a fix for this code. The exact error has been reported in player discussions; no dedicated official procedure for 0X00020004 is established in the sources available.

Try the low-risk launch checks first

1. Close Gray Zone Warfare and restart Steam. Exit Steam completely, reopen it, and launch the game from your Steam Library. If the error remains, restart the PC and try again. Restarts are player-reported troubleshooting, not a guaranteed fix.
2. Verify the game files. In Steam, open Library, right-click Gray Zone Warfare, select Properties → Installed Files → Verify integrity of game files. Let Steam finish, then launch the game again. A Steam discussion about this exact error reports this advice as coming from a developer, and MADFINGER also recommends verification for related launch problems: Steam discussion of the exact error and MADFINGER’s related Steam launch guidance.

Repair Easy Anti-Cheat only if the related setup issue applies

MADFINGER documents a setup procedure for the separate “Easy Anti-Cheat not Installed” error. It has not been confirmed as the solution to 0X00020004, but it is a relevant official repair to consider if EAC appears missing or damaged.

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1. Open the Gray Zone Warfare installation folder and then its EasyAntiCheat folder.
2. Locate EasyAntiCheat_EOS_Setup.exe. Copy its full path, then open Windows Run or a Command Prompt and run the executable with this argument: install 320d5d3f30f5495ebae73a8c74bc349d. For example, the command takes the form "fullpathtoEasyAntiCheat_EOS_Setup.exe" install 320d5d3f30f5495ebae73a8c74bc349d; replace the example path with the actual path on your PC.
3. Approve the Windows prompt if it appears, wait for setup to finish (MADFINGER says this can take up to 30 seconds), and relaunch the game.

Follow MADFINGER’s instructions for the “not installed” error if you need the documented procedure and screenshots. Do not treat it as a code-specific fix.

Check security software only when there is a reason to suspect interference

For other EAC errors, MADFINGER says Windows Defender or third-party antivirus can block game or anti-cheat components. Its related-error guidance identifies the GZW client, GZWClientEAC, and EasyAntiCheat_EOS.exe for firewall or antivirus allowances. A separate security-violation article also addresses antivirus interference. These pages do not establish that security software causes every 0X00020004 failure.

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If you have a relevant block or warning, use your security product’s documented exception controls and limit any allowance to the named game and EAC files. Do not turn off your firewall or antivirus as a general troubleshooting step. See MADFINGER’s guidance for EAC error 0x00020008 and its security-violation guidance for 0x00000022.

Avoid riskier community workarounds

Players discussing the exact message have also mentioned manually starting EAC setup and restarting Steam or the PC. These are individual reports, not verified universal fixes. Some posts suggest deleting files or registry entries, or disabling security tools; the official guidance cited here does not establish those steps as safe first-line remedies. Stick to verification and the scoped official procedures above rather than deleting system or game data based on an unverified post.

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Get game-specific help if the error continues

If Steam verification and applicable EAC or security checks do not resolve it, contact MADFINGER Community Care and include the exact error text, when it appears, and the steps you have tried. You can also consult Easy Anti-Cheat support, which directs players to the relevant game support channel. MADFINGER’s troubleshooting index covers multiple anti-cheat and Steam issues, but a dedicated article for 0X00020004 is not established here.

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