Question about my clients in Outlook 2003

[anthonyaudi]

Hello I have a problem with my Exchange server and my clients who are using outlook 2003

The problem is my users are able to get their mail via OWA however when they open their Outlook 2003 they get an error that says

"Cannot access default mailbox. Either the exchange server is down for maintenance or there are network problems"

It is weird because they can send and receive mail perfectly fine with OWA but Outlook 2003 does not work for them?

I checked my eventvwr on my server and the error I have is Error 13 Autoenrollment and error 16 Autoenrollment

Anyone ever experience this problem or know how to fix it (I don't want to reinstall Exchange server for this)