How to Fix Malformed Packet Detected for Project Zomboid

After adding mods to the server, it is a common issue to encounter frequent kicks due to a “Malformed Packet Detected” error, which can have different types. This can be triggered by certain mods, causing conflicts with the built-in anticheat. Fortunately, this issue has a straightforward fix.

Note

Build 42 uses named options such as AntiCheatPacketException. Follow How to configure anti-cheat on your Project Zomboid server and set the check that is kicking players to 3 (log only) or 4 (disabled). The steps below apply to Build 41 (legacy41).

Steps to Fix

1. Open the File Manager for your server
2. Navigate to .cache/Server
3. Select your ini. If you didn’t change the world name it will be dedicated.ini
4. Scroll down in the ini settings and find AntiCheatProtectionType
5. Change each numbered anticheat to false and then save the changes
6. Restart the server