How To Fix ‘Serialization Error Action Needed’ in Ready or Not

Troubleshooting "Serialization Error Action Needed" in Ready or Not

1. Verify Game Files

Begin by verifying your game files through Steam. Ensure Steam isn't in offline mode.

• Locate Ready or Not in your Steam Library.
• Right-click, select "Properties," then "Local Files," and finally "Verify Integrity of Game Files."

Steam will identify and redownload any corrupted or missing files. Retry launching the game. If the issue persists, proceed to the next steps.

2. Remove Mods

Outdated or incompatible mods, particularly those not updated for Unreal Engine 5 (post-July 2024), frequently trigger this error. To remove mods:

• Locate Ready or Not in your Steam Library.
• Left-click "Manage," then "Browse Local Files."
• Navigate to ReadyorNot\Content\Paks and delete the mod.io folder.

This will resolve the error, but you'll lose your mods temporarily.

3. Reinstall Mods (Selectively)

Reinstall mods individually to identify the culprit. Check each mod's update date on Nexus Mods, Mod.io, or its source. Only reinstall mods updated after July 2024 (when Ready or Not transitioned to UE5). Install one mod at a time, testing the game after each installation. If the error returns, the last installed mod is the cause and should be omitted.

4. Reinstall Ready or Not (Last Resort)

If all else fails, a clean reinstall of Ready or Not might be necessary. While less likely, hard drive corruption could also be a factor. However, outdated mods are the most common cause of this error.

Ready or Not is available now on PC.