Installing and Configuring the Active Directory Connector
Unlike in Exchange 2000, the Active Directory Connector (ADC) does not need to be installed until after the /forestprep command has run. This was designed so that only a single schema extension is required for upgrading to Exchange Server 2003, as opposed to the dual-extension of Exchange 2000.
After the prompt by the Exchange Deployment Tools, the ADC can be installed. The connection agreements in ADC are necessary to synchronize directory entries between the Exchange 5.5 and Exchange Server 2003 systems. Unlike in Exchange 2000, the Exchange Server 2003 ADC can be installed on a member server and is often installed on the first Exchange Server 2003 system in a site.
Organizations can ...