We are running Windows 2000 Server and Microsoft Exchange Server 2000. Our clients run Outlook 2000 and Outlook Express. Recently, whether coincidence or an after-effect of installing Norton Antivirus for Exchange NAVMSE 2.5, the clients running Outlook Express can't get into their mailboxes. There is a message returned saying the username or password is wrong, and when tried repeatedly, an error message is returned. Strangely though, if a new user is created, both Outlook and Outlook Express work properly. What could be wrong and how can I solve this problem?
I have not used NAVMSE 2.5, but I wonder if perhaps the installation of it somehow disabled POP3 access for existing users. You might check in Active Directory Users and Computers and verify that the POP3 protocol is still enabled for the affected users. If it is, check the POP3 server in Exchange System Manager to see if it has been changed or reconfigured (I don't think it would be disabled because you said new accounts work fine).
Dig Deeper on Exchange Server setup and troubleshooting
Related Q&A from SearchExchange Staff
Have a question for an expert?
Please add a title for your question
Get answers from a TechTarget expert on whatever's puzzling you.