I upgraded from Exchange 5.5 to 2000 SP3 over the weekend on a single Windows 2000 server. All but one mailbox transfered over just fine. The one that will not is still there, it's visible in the folder list, but the user cannot log onto it, the receive permission denied popup. It shows that the box was logged onto by the Administrator (me or server) at 4:00 am this morning, though I was not here. Is there any way to assign the permissions to this particular mailbox to her account? If I create a new mailbox with the same name, it just creates another mailbox, it does not access the existing one. I have a pre-upgrade backup of all mailboxes, can I restore it to the new mailbox being created?