Upgrading Exchange 5.x Connectors

When you upgrade an Exchange 5.x server to Exchange 2000 Server, the connection information for the Exchange 5.x X.400 connectors is preserved. Connection information for site connectors is also preserved in the equivalent Routing Group connectors when you upgrade an Exchange 5.x server. Some connection information may be lost for SMTP connectors when you upgrade an Exchange 5.x server. The setup log file contains details about connection information that is lost, if any.

Important   When upgrading an Exchange 5.5 server with an Internet Mail Connector configured to forward mail through a smart host, you should take note if the smart host resides in an Exchange 2000 administrative group that consists of multiple routing groups. In such a scenario, Active Directory Connector will designate the first routing group that it finds as the connected routing group for the upgraded SMTP connector (displayed on the connector's Connected Routing Groups tab). Even if the smart host is correctly identified by the SMTP connector, unless the correct routing group is chosen, all messages routed through the SMTP connector will result in NDRs. To prevent this, after migration, manually configure the SMTP connector with the correct connected routing group. (This only applies to administrative groups consisting of more than one routing group.)

Caution   Exchange 5.5 servers cannot recognize Exchange 2000 routing groups. Therefore, if you have any Exchange 5.5 servers configured as bridgeheads, avoid moving these servers from one routing group to another. Exchange 5.5 servers view a routing group as a single Exchange 5.5 site. Moving an Exchange 5.5 bridgehead into or out of a routing group may result in NDRs because the source bridgehead will not be able to find the target bridgehead. To avoid this, upgrade all bridgehead servers in your organization, or move connectors to servers that have already been upgraded.