A new demo has been added in the Exchange Server 2003 demo portion.The detail of this demo is

Title: How to Configure Mailbox Manager in a Mailbox Recipient Policy to Exclude Specific Message Classes in Microsoft Exchange Server 2003

Objective: The objective of this demo/tutorial is to teach you how to configure mailbox manager in a mailbox recipient policy to exclude specific message classes in Microsoft Exchange Server 2003. While configuring Mailbox Manager, it's easy to exclude folders from a mailbox recipient policy by clearing the check box beside the folder. If you clear Contacts, nothing in the default Contacts folder will be deleted or moved. However, you may want to exempt Contact Items that are stored in folders other than the default Contacts folder, or exempt Task Items that are stored in folders other than the default Tasks folder. The Message Classes feature allows you to exclude certain message classes from deletion, regardless of the folder they are stored in.

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