NT authentication fails when outlook clients attempt to connect to exc

[wish01]

Hi,
I am running exchange 5.5 SP4 on NT 4.0 environment.
My users have Windows 2000 pro and XP pro, running office 2000 and office XP.

All the sudden, outlook clients are prompted for user name, password and domain to access their mail box. The funny thing is that using their NT authentication doesn’t work.
But if I enter Exchange admin or Domain Admin credentials, Outlook will open their mail box as always.
I have uninstalled Outlook, clean all data and the registry on the client machine and the problem persists. My feeling is that something is wrong with the client authentication on NT.
Also, I have created a test mail box. When I go to the client machine to set up Outlook to open the mail box, I get to the point “verify user” and again I am prompted to enter user name, password and domain with same characteristics before.
Thank you for your help.
George

 

[dlstewart6759]

You might check to see if any local policy changes have happened. The Authenticated Users group will need to be able to Access This Computer From the Network attribute set for the Exchange server. If this group is not set to let the users authenticate, you not only will get the login box, but even entering the password will fail.

It is definately a rights issue, as the Admin accounts can get in without problems.

DLS

 

[wish01]

dlstewart6759
You are right on. I don't know how Authenticated Users got removed, but now they are back and everything is fine.
Thanks a lot!
George