1. Make sure you have the game updated with the last version (currently App Ver. 1.16 / Calibrations Ver. 1.16).
- Verify the files integrity of the game in Steam.
- Run the game through Steam with no mods, let it update your save file, then close it.
- Run the game, now with the mod.


2. If not fixed, try using Alt Saves mod https://www.nexusmods.com/eldenring/mods/2651


2. If still says corrupted save, try this tool https://www.nexusmods.com/eldenring/mods/9271




OTHER FIX ALTERNATIVES:

- If still says corrupted save, try using SeamlessCoop

- If still says corrupted save, try making a backup of your saves, then delete them, and try the first instructions again