Issue: Troubleshoot messages awaiting directory lookup in the exchange 2003 queue.

if you track the message you get retrying categorization on Exchange 2003.

When updating meeting sent to a distribution list or more than one user, the message is not being delivered and the sender will receive an undeliverable message a few days later (of course the meeting was never updated so you were wondering why no one showed up to your powerpoint presentation)
Your message did not reach some or all of the intended recipients.
Subject: NEW Weekly Sales Call beginning on 5/20
Sent: 5/24/2010 6:14 AM
The following recipient(s) cannot be reached:
xxxxx on 5/26/2010 6:35 AM
Could not deliver the message in the time limit specified. Please retry or contact your administrator.

Affects: exchange 2003; outlook 2003 and 2007
Solutions to the issue:

The problem is related to the way outlook 2007 and 2007 handle meetings. The Outlook 2007 client mangles the message headers, specifically for meeting request updates sent to distribution lists in GAL.

The headers are only mangled when you’re using Outlook 2007 on Exchange 2003. If you’re entirely a 2003 or 2007 front & back end, the hotfix is not needed.

You can read more and find the hotfix at http://support.microsoft.com/kb/938650/en-us

Note that you will need to restart the server after installing the hotfix and adding a registry key.

Comments:
Date of last update: 06-03-2010
Author:Gaetan Barthelemy

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