Why a clean sweep matters
Palworld 1.0 changed the engine build, the data tables and the mod plumbing all at once. Early Access mods that are left behind do not just stop working — they crash the game on boot or corrupt a save quietly. The only reliable update path starts from a clean game folder.
Delete the Early Access leftovers
Remove everything modding added before the update: the UE4SS files inside Palworld\Pal\Binaries\Win64 (dwmapi.dll, the UE4SS folder and the Mods folder), every custom .pak inside Palworld\Pal\Content\Paks and its ~mods subfolder, and any mod files placed next to the executable. When in doubt, delete the folders — Steam will restore the official files in the next step.
Update and verify the game
Let Steam or the Xbox app update Palworld, then run a file verification (Steam: Properties → Installed Files → Verify integrity) to replace anything you deleted by hand. Launch the game once, unmodded, and load your save to confirm the base game is healthy before adding anything back.
Reinstall only 1.0-compatible mods
Prefer Palworld's official mod loader and Steam Workshop for supported packages, then enable one dependency chain at a time. Reinstall a manual UE4SS or PalSchema build only when the author explicitly supports the current revision. Treat an Early Access package as incompatible until its author confirms otherwise.