Well, this script is the only bit I've not coded myself! grrr, and is causing me all the problems. When i try the same steps in I.E. I get a message saying 'connection problem' and a 'connection disgnosis' link. I guess it's just not a very common step of logic for people to take so nobody's reported it.
I'm still learning about sessions and have no idea what session register does :s
You're saying I should just remove it. I can see I need to study sessions more!
Having removed that line I still get the same connection error and the url in the address bar reads 'login.php' so I'm wondering if the $_SESSION['refer'] is causing me problems but I can't see how that could be.
Could it be as the logout script kills the session it removes my previously set up 'referer', that makes almost perfect sense really.