I can't seem to log out. In an attempt to log out and log back in as a member who is having a problem, I have found I can't log out.

I have tried logging out, closing the browser, and opening a new browser. As soon as I get back to our forum, I see I am still logged in. It works this way from both my bookmarked url, and from typing it in myself.

I know this problem. I encounter the same problem as I convert my 6.5.5 to 7.0
The problem comes from corrupt cookies/leftover old cookies. I clear out all cookies from the domain in my browser by hand (not with the clear cookie function from threads), close the browser, reopen and go to my site.

From this point the problem was gone for me and never come back.

Also worth having a different cookie prefix to your exisitng forums

Suppose that makes sense.