POP3 and Lotus Notes

First, for those stuck using Lotus Notes, I understand…. Getting something this simple to work should not take weeks.

Trying to access email through a POP3 client (Outlook or Outlook Express) – constantly getting the error “Unable to open mail file for USER/DOMAIN. File does not exist”. Considering the user uses Notes at work every day, his file is there. The POP3 and SMTP server is one and the same. Its Release 5, and as usual, Lotus knowledge-base search comes up with 100 thousand documents on what was fixed in every release since 3.0.4.

Is there anyone out there that can shed some light on this simple issue??