How to Fix GameGuard Initialize Error in Helldivers?

“GameGuard Error Code 120” in Helldivers 2 is an anti-cheat-related startup error that usually appears when the GameGuard service cannot initialize correctly or fails to communicate with the game during launch.

This error is most commonly reported after a game update, a failed or incomplete anti-cheat installation, corrupted GameGuard files, damaged local game data, Windows permission problems, missing runtime components, or interference from antivirus, firewall, overlay, or monitoring software.

1. Remove Helldivers 2 Data from AppData

Removing Helldivers 2-related folders from the AppData directories can help because these locations store local configuration files, cached data, and other profile-specific files used during startup. If any of that local data becomes corrupted or outdated after an update or failed launch, it can interfere with GameGuard initialization and trigger Error Code 120.

Deleting those folders forces the game to recreate fresh local data the next time it launches.

1. Press Windows + R to open the Run dialog.
2. Type %appdata% and press Enter.
3. In the Roaming folder, look for any folder related to Helldivers or Helldivers 2.
4. Delete the matching folder if you find one.
5. Now go back one step, click AppData in the address bar, and open the Local folder.
6. Again, look for any Helldivers or Helldivers 2-related folder.
7. Delete it if present.
8. Restart your PC.
9. Launch Helldivers 2 again and let it recreate fresh local files.

2. Verify the Integrity of Game Files

Verifying the game files helps because GameGuard Error 120 can also appear when Helldivers 2 is missing required files or when recently updated files were installed incorrectly. Steam compares your installed game files with the official version and re-downloads anything that is missing, corrupted, or incomplete.

This is one of the safest fixes to try because it repairs the installation without removing your save data.

1. Open Steam.
2. Go to your Library.
3. Right-click Helldivers 2 and select Properties.
4. Open the Installed Files tab.
5. Click Verify integrity of game files.
6. Wait for Steam to finish scanning and repairing the installation.
7. Restart Steam and launch Helldivers 2 again.

3. Test the Game from a Different Windows User Account

Trying the game from another Windows account can help determine whether the issue is tied to your current user profile. In some cases, corrupted profile data, broken permissions, or account-specific startup settings can prevent GameGuard from loading correctly even though the game files themselves are fine.

This is not the most common cause, but it is useful as a diagnostic step if the error only happens on one Windows account.

1. Open Settings and go to Accounts.
2. Click Other users, then select Add account.
3. Click Add account.
4. Enter the sign-in details for another account, or create a new local account if needed.
5. Sign out of your current Windows account.
6. Sign in to the newly created or alternate account.
7. Open Steam, launch Helldivers 2, and check whether Error Code 120 still appears.

4. Reinstall GameGuard and Whitelist the Game Folder

Reinstalling GameGuard can help because Error Code 120 often appears when the anti-cheat files are corrupted, incomplete, or blocked during startup. Security software can sometimes quarantine, block, or silently interfere with GameGuard files, which prevents the anti-cheat service from loading normally.

Deleting the existing GameGuard folder forces Helldivers 2 to download a fresh copy. Adding the game folder to your antivirus or firewall exclusions can also prevent future interference.

1. Close Helldivers 2 and fully exit Steam.
2. Open the Helldivers 2 installation folder. For most Steam installs, it is usually in:
   C:\Program Files (x86)\Steam\steamapps\common\Helldivers 2
3. Inside that folder, look for the GameGuard folder.
4. Delete the GameGuard folder.
5. Launch the game again so Steam and Helldivers 2 can reinstall the missing GameGuard files automatically.
6. Open your antivirus settings or Windows Security.
7. Add the main Helldivers 2 installation folder to the exclusions or whitelist list.
8. If your security software allows folder-based exclusions, add the GameGuard subfolder as well.
9. Also allow Helldivers 2 and GameGuard through Windows Firewall.
10. If you use third-party antivirus software, check its quarantine or protection history for blocked GameGuard files.
11. Restart your PC and test the game again.

5. Repair the Microsoft Visual C++ Redistributables

Repairing the Microsoft Visual C++ Redistributables can help because Helldivers 2 and related startup components rely on Microsoft runtime libraries to launch correctly. If those runtime files are missing or damaged, the game or GameGuard may fail during initialization.

Repairing the installed packages restores those dependencies without affecting your personal files.

1. Press Windows + R, type appwiz.cpl, and press Enter.
2. In the list of installed programs, locate every entry named Microsoft Visual C++ Redistributable.
3. Right-click each entry and select Change.
4. Click Repair and complete the process for each supported entry.
5. If the repair option is unavailable for an entry, uninstall it first.
6. Download the latest supported Visual C++ Redistributable packages for both x64 and x86 from Microsoft’s official website.
7. Install them, restart your PC, and launch Helldivers 2 again.

6. Set Compatibility Mode to Windows 8

Setting compatibility mode to Windows 8 is not a primary fix, but it has helped some users when GameGuard failed due to a startup compatibility issue on their current Windows installation. Since anti-cheat software can behave unpredictably with compatibility settings, this should be treated as a later workaround rather than an early fix.

Try this only after the earlier methods fail.

1. Go to the Helldivers 2 installation folder.
2. Right-click helldivers2.exe or the main game executable and select Properties.
3. Open the Compatibility tab.
4. Check Run this program in compatibility mode for.
5. Select Windows 8 from the dropdown menu.
6. Click Apply, then OK.
7. Launch the game and see whether Error Code 120 is resolved.

If the error still continues after trying all of the methods above, close overlay, monitoring, and injection-based background tools such as MSI Afterburner, RivaTuner Statistics Server, Discord Overlay, NVIDIA overlay, or similar software, then test the game again. These tools can sometimes interfere with GameGuard during startup.

If nothing changes, perform a clean boot to start Windows with only essential services and check whether a third-party background program is causing the conflict. If the game works in a clean boot state, re-enable services and startup items gradually until you find the conflicting software.

As a final measure, reinstall Helldivers 2 completely through Steam. A full reinstall is worth trying if GameGuard files, startup components, or game data remain damaged even after verification and manual cleanup.