This ini setting: [Archive] bInvalidateOlderFiles=0 -> change 0 to 1 This is what worked for me! I was having the same papyrus.ini error from SkyUI and also had no MCM functioning. Also Inventory screens had 5 sec delays coming up. This one quick change fixed it all! Thanks so much! To clarify: Documents\My Games\Skyrim\Skyrim.ini --> [Archive] section --> binvalidateOlderFiles=0 --> change 0 to 1 BLAMMO! FIXED!