Article ID: 975990 - View products that this article applies to.
You archive e-mail messages to a Microsoft Exchange Server 2007 mailbox from an external system or by using Exchange Server 2003 Standard Journaling. In these scenarios, e-mail messages that contain the same message ID are discarded, and only the oldest copy of each e-mail message remains in the mailbox.
This issue occurs because Exchange 2007 uses the Duplicate Detection function during the archiving of e-mail messages. In some cases, the original e-mail message may have been split into multiple copies, each with the same message ID. When Exchange 2007 receives these messages for archiving into a single mailbox, messages that have the same message ID as a previously received message are discarded.
For more information about Message Journaling in Exchange 2007, see the following TechNet articles:
More Powerful Journaling in Exchange 2007
How to Create a New Journal Rule
For Exchange Server 2007To resolve this issue, download and install Update Rollup 2 for Exchange 2007 Service Pack 2.
PrerequisitesThe following list contains prerequisites for the update rollup:
(http://support.microsoft.com/kb/972076/ )Description of Update Rollup 2 for Microsoft Exchange Server 2007 Service Pack 2
For Exchange Server 2003For more information about how to resolve this issue for Exchange Server 2003, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/971660/ )E-mail messages from certain external domains that have several recipients only have one archived copy instead of several archived copies after you enable the BCC Journaling feature on an Exchange Server 2003 server
After you install the update rollup, you must make changes to the registry on the server that is running Exchange 2007.
Two registry subkeys control the Duplication Detection function in Exchange 2007. The subkeys are ParametersPrivate and ParametersPublic.
Important Disabling duplicate detection on a Mailbox server enables any message to be delivered to a recipient with a duplicate message ID. We recommend that you make this change only on Mailbox servers that contain Journal mailboxes and no other mailboxes.
Article ID: 975990 - Last Review: January 22, 2010 - Revision: 1.0