Applies to: Exchange Server 2010 SP3, Exchange Server 2010 SP2

Topic Last Modified: 2010-07-29

The Microsoft Exchange Server 2010 Mailbox server role can coexist with Exchange Server 2003 and Exchange 2007. If you're upgrading from an Exchange 2003 organization to Exchange 2010, the first server role you need to upgrade is the Client Access server role.

Then, after Mailbox servers have been deployed, you can move mailboxes from Exchange 2003 to Exchange 2010. To move mailboxes to Exchange 2010, you can use either the move request cmdlets or the Exchange Management Console, depending on your Exchange version. For more information about how to move mailboxes, see the following topics:

Move Mailboxes from Exchange 2003 Servers to Exchange 2010 Servers

Move Mailboxes from Exchange 2010 Servers to Exchange 2003 Servers

Exchange 2003 and Exchange 2010 Coexistence

The following topics provide more details about Mailbox server role feature coexistence between Exchange 2003 and Exchange 2010:

Understanding Public Folders

Understanding Exchange Search

Understanding E-Mail Address Policies

For more information about upgrading from previous versions of Exchange, see the following topics:

Exchange 2007 - Planning Roadmap for Upgrade and Coexistence

Exchange 2003 - Planning Roadmap for Upgrade and Coexistence