native mode
Technology› E-mail› Microsoft Email› Microsoft Exchange
Microsoft Exchange 2003
An operating mode of Exchange Server 2003 when the Exchange organization consists of only Exchange 2003 or Exchange 2000 servers. Servers running Exchange 5.5 and earlier versions cannot join an organization running in native mode. [Exchange 2003]
Technology› E-mail› Microsoft Email› Microsoft Exchange
Microsoft Exchange 2007
A native mode organization can contain only servers running Exchange 2000 Server, Exchange Server 2003, or a combination of both versions. Servers running Exchange Server 4.0, Exchange Server 5.0, or Exchange Server 5.5 cannot be introduced into the organization. By default, Exchange 2000 Server and Exchange Server 2003 are installed in mixed mode. However, by switching to native mode, you gain access to more features. [Exchange 2007]
Technology› Operating System› Microsoft Windows› Microsoft Windows Server
Microsoft Active Directory
When all the domain controllers in a given domain are running Windows 2000 or when all the domain controllers in a given domain are running Windows Server 2003. This mode allows organizations to take advantage of Active Directory features such as Universal groups, nested group membership, and inter-domain group membership.