The successful deployment and management of Active Directory has been a fundamental prerequisite for Exchange since Exchange dropped its own directory service in Exchange 2000. In fact, Active Directory shares many of the characteristics of the older Exchange directory services, and there is no doubt that Microsoft learned a lot about how to design and operate directories from the experience gained with Exchange 4.0 to Exchange 5.5.
The strong link between Exchange and Active Directory
By any measure, Exchange makes the most extensive use of Active Directory of any Microsoft application. The Exchange installation procedure does the following:
Extends the Active Directory schema to add a large number of new objects and attributes ...