what permission setting should the warning file be?
when i try warn someone it says i dont ave enough permission
Go to: ACP Users and Groups > Groups > Yur usergroup > Edit > Miscellaneous Tab > Warning System > and Tick the "Can send warnings to other users?" option checkbox.
A permissions error like this is nothing to do with the permissions of the file, it's a MyBB error, thus it's the user permissions that Yaldaram explained.