Fix for "Unexpected Error" on Existing/New Save
Hey guys, if you are running a save or server on B42.13 and are logging into it and seeing some error that says "Unexpected Error, see Console for details, you might be getting an error like so:
"WorldSimulation.reflectionInit(WorldSimulation.java:104). Stack trace:"
If you are getting this, what fixed this for me was the following.
This will erase all your local data. Please make sure if you have a server/save running files from here that you save it from these files before deleting them
- Uninstall PZ from steam.
- Go to the folder PZ was saved in, such as "...\steamapps\common\projectzomboid*"* and delete this file and everything in it
- Go and delete your Zomboid folder found usually at C:\Users*your user\Zomboid
From here I reinstalled the game, connected to my B42.13 server that has like 80 mods on it by the way and reinstalled all the mods. Launched right up no issues and works just fine.
(Mods included car mods, UI, health, guns, the whole thing so I am confident this would be people's fixes)
Posted Feb 16, 2026, 8:33 PM UTC
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