The server was unable to save the format this time. Please try again

Question

In a list of SP2016 site one user is not able to save the add new item form. User is getting :

The server was unable to save the format this time. Please try again

Previously user was able to add items. The list has no unique permission and user has edit permission on site. Meanwhile other users are able to add entries.

UPDATE : When user is trying to edit the existing item and save, it is giving

access is denied. You don't have permission to perform this action or access the resource

Any leads please.

Answer 1

This issue generally comes when you have unique permissions, but you've already ruled that out.

One more check remains - have the user/group added in visitors group (if not added) and the try it again. Should work!