exchange 2003 with Outlook2003-2007, Outlook Express on XP/Vista and Win7, and various smart phones. Need to know how to configure Exchange to authenticate with e-mail address, instead of domain\username. Everything works fine with domain\username login. I thought domain\username and e-mail address were interchangable in a default installation with POP3 enabled but MS Support says that this isn't possible and I just need to reconfigure every client with the domain\username - I am not sure if I have a problem or just lack the know-how. I need this to seamlessly move 30 POP3 users over from on-line hosting, All users already have clients configured with e-mail address. I plan to then systematically move them to a secure login method. I am also wondering if I should forget the whole POP3 setup and go straight to IMAP, SPA or some other type of secure login. Any info you can provide will help. Thanks in advance.Henry Castillo

Exchange has never supported the use of the email address for the login, despite appearances. What usually happens is that people will set the UPN value of the domain to match the email address domain. You can see the current UPN on the properties of a user in ADUC on the Account tab. The username is then configured to match the email address. You can add additional UPN suffixes through AD domains and trusts. However I would test the change of the UPN value before you make the mass change. Remember to allow enough time for the domain and Exchange to see the modification before declaring it a success - so at least 48 hours. However if the user accounts have different usernames to email addresses, so username is jsmith, email address is john.smith, which is pretty common, then you are going to run in to issues getting everything to match the email address. Windows and Exchange doesn't always react well to usernames being changed and it is something I tend to avoid where possible. Exchange is using AD to authenticate, it doesn't authenticate itself. An ISP based system basically matches the email address and username by default, because that is how *nix systems work. There isn't that connection with Exchange. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources

And more information about the POP3 logon credentials,please see: Understanding login strings with POP3/IMAP http://msexchangeteam.com/archive/2004/03/31/105275.aspx Frank Wang TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Hi Henry, Any updates on your issue?Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

I have access to the test lab tonight. Will post tomorrow.Henry Castillo