Hello, I have a curious situation. I just created a new AD account and created an exchange mailbox for it. I have enabled the account to use IMAP. However when I attempt to logon with username and password the logon is rejected. Logging on with domain\username also is rejected. However logging on with username@domain (The User Principal Name or UPN) works Where: domain is the full qualfied domain name for the logon domain works. My other user accounts don't have to go through this. My question is what may have caused this account to be require the UPN form for the username? Thanks William Holmes (MCP) Department of Computer Science 310 Upson Hall Cornell University Ithaca, NY 14853 wtholmes@xxxxxxxxxxxxxx 607 255-1757 (o) 607 227-6049 (c)