User Posting Bug

[Edward Ghost]

Hello, I've been experiencing a bug with my users.
When some of them log in, it shows them as being logged on in my "Online" sidebar,
but on the "Who's Online" page it shows them as a guest,
and when they post, they are called a guest in the post.

Optimizing my database tables fixed it temperarily once, as "Who's Online" displayed it correctly,
but when they posted it still said guest, and when they logged off and logged back in
it said guest again.

[Edward Ghost]

Also, at the board indexes, it shows the users display name next their posts, and it's clickable and goes to the right profile, yet when you click into the message, it shows it as posted by a guest but with the right username, and the users can also edit these posts, which I find a little odd.

Can anyone help me out?

[Edward Ghost]

I spoke to [unknown] about this issue, and he said "the user data reference is not sticking".