The topics in this section describe the modifications Microsoft® Exchange Server 2003 makes to existing Microsoft Active Directory® classes and attributes, and the classes and attributes Exchange Server 2003 adds to Active Directory.

The Schema Changes Between Exchange 2000 and Exchange 2003 section outlines the differences made to the Exchange Server 2003 schema since Exchange 2000 Server.

The Exchange Server 2003 Schema Changes section includes all of the schema changes that are made when you install Exchange Server 2003.