The messaging interface has returned an unknown error. If the problem persists, restart Outlook.

"The messaging interface has returned an unknown error. If the problem persists, restart Outlook." When I get this error when starting the MS Outlook program, I know I can fix this issue right away by rebuilding the Outlook profile of the user.

Let me know if this is the same to you.

Another Outlook misconfigured setup is "Can't contact LDAP Directory Server (81)". If you are not using LDAP Directory Server for your exchange server, of course this is an obvious configuration error (maybe not).

Here's how to correct your MS Outlook configuration (KB 836205)

1. Start Outlook, on the Tools menu, click E-mail Accounts.
2. Under Directory, click View or change existing directories or Address Books, and click Next.
3. Under Directories and Address Books box, click the LDAP address book that you want to remove (delete), and then click Remove. Finish
4. Get out of Outlook, and restart again.

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