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

Ready or Not, while sounding deceptively innocent, delivers a hardcore SWAT FPS experience, both solo and multiplayer. However, even seasoned operators can encounter technical hiccups. This guide tackles the frustrating "Serialization Error Action Needed" in Ready or Not.

The dreaded "Serialization Error Action Needed" often appears alongside "Corrupt data found, please verify your installation." This is a common Unreal Engine error, and thankfully, there are a few solutions.

1. Verify Your Game Files

The first step, as the error suggests, is to verify your game's integrity. Ensure Steam isn't in offline mode. Here's how:

1. Open your Steam Library and locate Ready or Not.
2. Right-click the game and select "Properties."
3. Click "Local Files," then "Verify Integrity of Game Files."

Steam will scan for missing or corrupted files and automatically redownload them. Try launching Ready or Not again. If successful, problem solved! If not, proceed to the next step.

2. Remove Mods

Outdated or incompatible mods are a common culprit behind this error, especially since the transition to Unreal Engine 5. To remove mods:

1. Open your Steam Library and locate Ready or Not.
2. Click "Manage," then "Browse Local Files."
3. Navigate to the `ReadyOrNot\Content\Paks` folder.
4. Delete the `mod.io` folder.

This will disable all your mods. The game should now run, but you'll need to reinstall your mods selectively, as detailed below.

3. Reinstall Mods Selectively

Reinstall your mods one at a time. Check the update date on Nexus Mods, Mod.io, or your mod source. Mods updated after July 2024 (when Ready or Not switched to UE5) are more likely to be compatible.

Install a mod, test the game. If the error returns, the last installed mod is the problem; skip it. Unfortunately, pre-UE5 mods are usually incompatible.

Last Resort: Reinstallation

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 However, outdated mods are the most frequent cause of this error.

Ready or Not is available now for PC.