This error usually shows up when the game’s IoStore files are mismatched or corrupted, basically, the global.utoc doesn’t line up with its .ucas or other chunks. The quickest fix I’ve seen work is verifying game files (Steam/Epic), which re-downloads any broken chunks. If you’re using mods or custom pak/utoc files, remove them first because they often cause this exact issue. Also, make sure you didn’t mix files from different game versions or updates. If it still happens, a clean reinstall (after deleting leftover game folders) usually sorts it out.