How To configure Collaboration Services in an environment with a Shared SMTP Namespace. (4258117)

How To configure Collaboration Services in an environment with a Shared SMTP Namespace.

How should Collaboration Services be configured in an environment where sites use the same Primary SMTP namespace?

In some shared namespace configurations each Microsoft Exchange organization is configured as authoritative for the shared namespace.  This configuration will prevent Exchange from properly redirecting email for stub objects to the correct synchronization partner sites.

In an environment where sites use the same Primary external namespace, a second SMTP namespace should be configured for routing mail between the sites. 

SMTP mail must be able to properly send between each site and it's partners secondary SMTP domain.

At each site perform the following:

1. In the collaboration services console right click "Collaboration Services" at the top of the navigation tree
2. Select Properties
3. Navigate to "Synchronization | Active Directory | Namespaces"
4. Remove the Shared namespace by highlighting it and clicking the remove button
5. If necessary add the secondary SMTP domain namespace to the top of the list.
6. Republish all Active Directory object collections at each site.

Collaboration Services will now stamp the secondary SMTP namespace as the TargetAddress attribute on the stub objects at any subscribing partner sites.  This secondary SMTP namespace will then be used to redirect mail to the correct Microsoft Exchange Organization.