Exchange Unified Messaging

Microsoft Office Communications Server 2007 and Microsoft Office Communications Server 2007 R2 will reach end of support on January 9, 2018. To stay supported, you will need to upgrade. For more information, see Resources to help you upgrade your Office 2007 servers and clients.

Exchange 2007 Unified Messaging (UM) is one of several server roles that you can install and configure on a computer that is running Microsoft Exchange Server 2007. For stand-alone Enterprise Voice deployments, Unified Messaging combines voice messaging and e-mail messaging into a single store that is accessible from a telephone (Outlook Voice Access) or a computer. Unified Messaging and Office Communications Server work together to provide call answering, Outlook Voice Access, and auto attendant services to departmental and greenfield Enterprise Voice deployments.

For these features to be supported, you must be running Exchange Server 2007 Service Pack 1 (SP1).


Exchange Unified Messaging may not be required for Enterprise Voice deployments with PBX integration, because the PBX can continue to provide voice mail and related services to all users. For details, see Enterprise Voice Deployment Options in Planning and Architecture documentation.

Features of Unified Messaging and Office Communications Server

Using Exchange Unified Messaging with Office Communications Server provides several benefits, as listed in this section.

Call Answering

Call answering is the taking of voice messages on behalf of users whose extensions are not answered or are busy. It includes playing a personal greeting, recording a message, and submitting the message to the Exchange Hub Transport Server to be queued up for delivery to the user's mailbox, which is stored on the Exchange mailbox server.

If a caller leaves a message, the message shows up in the user's inbox. If a caller chooses not to leave a message, a missed call notification is stored in the user's mailbox. Users can then access their inboxes using the Microsoft Office Outlook messaging and collaboration client, Outlook Web Access, the Exchange ActiveSync technology, or Outlook Voice Access. The subject and priority of calls can be displayed in a way similar to that of e-mail.

Outlook Voice Access

Outlook Voice Access enables an Enterprise Voice user to access not just voice mail, but also the Exchange inbox, including e-mail, voice messages, calendar, and contacts from a telephony interface. The subscriber access number is assigned by an Exchange Unified Messaging administrator.

Auto Attendant

An auto attendant is a feature of Exchange 2007 Unified Messaging that can be used to configure a phone number that outside users can dial to reach company representatives. In particular, it provides a series of voice prompts that assist an external caller in navigating a menu system. The list of available options is configured on the Exchange Unified Messaging server by the administrator.

Fax Services

Exchange Unified Messaging includes fax features, which enable users to receive incoming faxes in their Exchange mailboxes. For details, see “Unified Messaging” in the Microsoft Exchange Server documentation at

Working Together

To provide the features and services described previously in this section to your Enterprise Voice users, you must deploy the following Exchange Server 2007 server roles:

  • Unified Messaging Server, which provides a single storage location for e-mail and voice mail. The Unified Messaging Server connects Exchange Server 2007 with Office Communications Server 2007 R2.

  • Hub Transport Server, which routes e-mail messages from the Unified Messaging Server to user mailboxes.

  • Client Access Server, which hosts client protocols, such as Post Office Protocol 3 (POP3), Internet Message Access Protocol 4 (IMAP4), Secure Hypertext Transfer Protocol (HTTPS), Outlook Anywhere, Availability service, and Autodiscover service. The Client Access Server also hosts Web services.

  • Mailbox Server, which hosts user mailboxes.