Outlook 2000 popserver and username changing

I am running XP Pro with Office 2000 sp3, my username and pop server keep getting changed by something on my system and at least two other users. The popserver changes to 127.0.0.1 and the username changes to username/popserver. Has anyone run into this problem before? If so how can I stop it from happening. I think the change is happening at a certain time when Outlook is shutdown. It does not seem to change when Outlook is already open.