Role of Groups and Access Control Lists in Exchange 2000 Deployments — Exchange 2000 relies on Microsoft Windows 2000 groups and the Microsoft Active Directory directory service for both access control and distribution tasks. Familiarize yourself with the differences between Windows 2000 groups, distribution lists in Exchange Server 5.5 and earlier, and Microsoft Windows NT groups in this article. With careful planning, you can migrate your existing Exchange distribution lists to the corresponding Windows 2000 groups, while retaining their functionality.

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