Very strange problem...
Using Outlook 2000, SR-1. In the Folder List view, other employee mailboxes show up without being added in Outlook anywhere. I cannot do anything with them, expand or delete. Most users have this problem. Additional added mailboxes are randomly added.
This also shows up on Exchange Server under the Logons in Private Information Store. Nothing can be done here either to remove the entries.
I've tried a few searches on MSKB and TechNet but came up empty.
I've included 3 GIF screen shots. Any ideas?