If you plan to host user mailboxes and\or public folders on a server, the Mailbox server role must be installed on the server.

In Microsoft Exchange Server 2007, the Mailbox server role is one of five server roles that you can install and then configure on a computer. The Mailbox server role hosts mailbox and public folder databases. It also hosts the offline address book. Finally, you can configure address lists and managed folders from a Mailbox server.

The Mailbox server interacts with other server roles in your deployment and with the Active Directory service servers in order to provide and retrieve the following types of information:

  • The Mailbox server retrieves user account information, recipient properties, address list information and e-mail address policy information from the Active Directory server.
  • The Store driver on the Hub Transport server places messages from the transport pipeline into the appropriate mailbox. The Store driver on the Hub Transport server also adds messages from the Outbox of a sender on the Mailbox server to the transport pipeline.
  • The Client Access Server sends requests from clients to the Mailbox server, and returns data from the Mailbox server to the clients. The types of data that the Client Access server sends between the client and the mailbox server are messages, free and busy data, and client profile settings.
  • The Unified Messaging server retrieves e-mail and voice mail messages and calendar information from the Mailbox server for Outlook Voice Access. The Unified Messaging server also retrieves storage quota information from the Mailbox server.
  • Outlook clients that are inside your firewall can access a Mailbox server directly to send and retrieve messages.

For more information about Mailbox server, see Microsoft Exchange product document Mailbox.

New Mailbox Features

Hosted Messaging and Collaboration version 4.5 includes the creation, management, and deletion of Resource Mailboxes. Using the new CreateResourceMailbox, ModifyResourceMailbox, and DeleteResourceMailbox procedures through either the Hosted Email 2007, or Managed Email 2007 namespaces you can create and manage both room and equipment Resource Mailboxes.

Microsoft Exchange Server 2007 Service Pack 1 (SP1) introduces the following new features for the Mailbox server role:

  • Public folder management improvements, including the new Public Folder Management Console
  • New public folder features
  • Mailbox management improvements
  • Ability to import and export mailbox data to .pst files
  • Changes to messaging records management (MRM)
  • New performance counters for online database defragmentation

The ability to import and export mailbox data to .pst files is closely related to Hosted environment, see Mailbox Server Role Improvements for more related information.

For detailed description about these new features, see New Mailbox Features in Exchange 2007 SP1.