MyBB Community Forums

I'm attempting to switch my forums from example.com/forums to forum.example.com.

I've switched:

Board URL - http://forum.example.com
Cookie Domain - (empty/blank)
Cookie Path - /
Cookie Prefix - (empty/blank)

I'm still unable to login to either of these but the database is working (I have my board offline and it is grabbing the message from the DB, also says I successfully logged in but its not storing the cookie).

What do I need to do to get this to work?

use cookies as per login logout problems ... guidance

EDIT - Had to go into settings.php manually and fix it...read over that paragraph apparently :p