We have exchange 2003, and all users are using OE 2000. Normally, when a user wishes to email another internal user, they enter the users initials (username), and outlook then resolves the contact and displays the email address in full. However, there are 2 users who this refuses to work with. You enter the initials (their username) in the 'to' field for either of these users, and it refuses to resolve. I've had a check on the MS support page and have found nothing. Anyone have any ideas?