If this still doesn't solve your problem, then it may also be possible that the user's mailbox is hidden from the Exchange Server address list. To check this, open Active Directory Users and Computers, select the Exchange Advanced tab on the particular user's properties sheet, and verify that the "Hide From Exchange Address Lists" checkbox is not selected.
If Microsoft Outlook still does not authenticate the account name, then try accessing the mailbox using Outlook Web Access (OWA) or from a different workstation. Can you log on? This may provide further insight into whether the problem is workstation- or server-based.
Do you have comments on this Ask the Expert Q&A? Let us know.
Related information from SearchExchange.com:
Dig Deeper on Exchange Server setup and troubleshooting
Related Q&A from Bradley Dinerman
Find out how you can avoid DNS issues related to a Exchange 2003 server only collecting email from specific POP3 domains. Continue Reading
Are you having trouble with duplicate appointments in your Microsoft Outlook 2003 calendar? Learn what may cause this to happen. Continue Reading
Learn the best way to configure the default recipient policy in an Exchange 2003 test environment. Continue Reading
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.