Applies to: Exchange Server 2010 SP1

Topic Last Modified: 2012-07-23

Estimated time to complete: 10 minutes

The Exchange 2010 hybrid server that you're introducing to your Exchange 2003 organization will handle mail transportation and routing of messages. Therefore, you'll need to modify the e-mail address policy for your users and mail-enabled objects. Adding a shared service-routing namespace as a custom secondary e-mail domain for your recipients enables them to receive e-mail messages that use the service routing namespace.

Learn more at: Understanding Shared and Split SMTP Namespaces

This topic is meant to be read as part of the Microsoft Exchange Server 2003 and Office 365 Hybrid Deployment checklist. Information or procedures in this topic may depend on prerequisites configured in topics earlier in the checklist. To view the checklist, see Checklist - Exchange 2003 and Office 365 Hybrid Deployment.

How do I do this?

You need to be assigned permissions before you can perform this procedure. To configure email address policies in Exchange 2003, you must be a member of the Exchange Full Administrator or Exchange Administrator groups.

You can update your existing recipient e-mail address policy using Exchange System Manager in Exchange 2003.

  1. In Exchange System Manager, navigate to Recipients > Recipients Policies for your organization.

  2. Right-click the e-mail address policy you want to update, and then click Properties.

  3. In the Policy Properties dialog, click E-Mail Addresses (Policy). The Generation rules for the e-mail address policy are listed.

  4. Click New to add a service-routing namespace to the e-mail policy.

  5. In the New E-Mail Address dialog, select SMTP Address from the addresses listed in the E-mail address type pane. Click OK to continue.

  6. In the SMTP Address Properties dialog, enter the SMTP service-routing namespace with the "@" symbol as a prefix in the Address field. For example, "".

  7. Clear the This Exchange Organization is responsible for all mail delivery to this address check box. Click OK.

  8. Select the check box next to the domain you just added to the Generation rules list, and then click OK.

  9. Click Yes in the Exchange System Manager dialog to update all corresponding recipient e-mail addresses with the new custom namespace and to complete the procedure.

How do I know this worked?

After you've added the new namespace to the e-mail address policy and waited for the policy to update, you should see the namespace in each recipient's e-mail address list. For example,

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