Connecting to Other Messaging Systems

Upgrading Exchange 5.5 Connectors

Upgrading from Exchange 5.5 to Exchange 2000 involves several basic steps:

Upgrade your operating system from Windows NT 4.0 to Windows 2000.
Populate Active Directory with all of the data from the Exchange 5.5 directory by installing and running the ADC that comes with Exchange. (You must use this version, rather than the version that comes with Windows 2000.) When you import the Exchange directory to Active Directory, Exchange 5.5 import containers that hold custom recipients are replicated into Active Directory. Custom recipients become contact objects.
Install Exchange 2000, being sure to install your connectors.

Reconfiguring the Connectors

When you upgrade from Exchange 5.5 to Exchange 2000, you must reconfigure the Exchange 2000 connectors. Although the connection settings are saved, you need to reconfigure the following:

Schedule of directory synchronization.
Address space used for message routing.
Import container and export containers.
Note Trust level information on Exchange 5.5 import and export containers is obsolete in Exchange 2000, and is deleted during upgrade.
Delivery restrictions such as message size.

Transfer of Ownership of Directory Entries

A connector can be said to own the directory entries that it imports from another messaging system. When you populate Active Directory, the new contact objects are still owned by the Exchange 5.5 connector. The msExchImportedFrom attribute on these entries is populated by the globally unique identifier (GUID) of the original Exchange 5.5 connector.

The Exchange 2000 connector takes over ownership of these former custom recipients as follows:

After the upgrade to Exchange 2000, on each inbound directory synchronization cycle, the Exchange 2000 connector checks the value of the msExchImportedFrom attribute. If the value is a close match to an Exchange 5.5 connector GUID, the new connector stamps the attribute with its own GUID, thus replacing the original GUID.

Effects of Ownership on Import and Export

You should always let a connector populate Active Directory with foreign users rather than create them manually. Changes made in a foreign directory are not imported to Active Directory unless the connector has imported, and therefore owns, the associated entries. (This is true even if the entry is in the designated import container.)

On export, the situation is reversed. When a connector exports directory entries from Active Directory, the connector propagates changes to any entries within its export containers that it does not own. Specifically, these entries do not contain the connector's GUID in their msExchImportedFrom attribute. This includes manually created entries that represent foreign users, and users native to Exchange.

Important Exchange connectors cannot create native entries in partner directories. In other words, you cannot master a partner directory from Active Directory.