Applies to: Exchange Server 2013, Exchange Online
Topic Last Modified: 2013-02-22
You can allow UM-enabled users to receive voice messages from anonymous callers or prevent them from doing so. By default, when users are enabled for Unified Messaging (UM) and voice mail, they can receive calls that are anonymous and don't contain caller ID information.
In most cases, calls received by Exchange servers contain a caller ID that can be used to determine the source of the incoming call. However, incoming calls may not include caller ID information for the following reasons:
- Your organization's telephony equipment is configured not to
include caller ID information.
- The incoming call is from a mobile or external telephone.
- The caller has disabled caller ID on their telephone.
Because the AnonymousCallersCanLeaveMessages parameter is enabled by default, a UM-enabled user can receive a voice message even if caller ID information isn't included. If the AnonymousCallersCanLeaveMessages option is disabled, and the UM-enabled user receives a call that doesn't include a caller ID, the call will be identified as anonymous, and the UM-enabled user won't receive a voice message.
For additional management tasks related to users who are enabled for voice mail, see Voice Mail-Enabled User Procedures.
What do you need to know before you begin?
- Estimated time to complete: 2 minutes.
- You need to be assigned permissions before you can perform this
procedure or procedures. To see what permissions you need, see the
"UM mailboxes" entry in the Unified Messaging
Permissions topic.
- Before you perform this procedure, confirm that a UM dial plan
has been created. For detailed steps, see Create a UM Dial
Plan.
- Before you perform this procedure, confirm that a UM mailbox
policy has been created. For detailed steps, see Create a UM Mailbox
Policy.
- Before you perform this procedure, confirm that the user's
mailbox has been UM-enabled. For detailed steps, see Enable a User for Voice
Mail.
- For information about keyboard shortcuts that may apply to the
procedures in this topic, see Keyboard Shortcuts in
the Exchange Admin Center.
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| Having problems? Ask for help in the Exchange forums. Visit the forums at: Exchange Server, Exchange Online, or Exchange Online Protection. |
Use the Shell to prevent voice messages from anonymous callers from being received
This example prevents UM-enabled user tonysmith@contoso.com from receiving voice messages from calls that don't contain caller ID information.
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Set-UMMailbox -Identity tonysmith@contoso.com -AnonymousCallersCanLeaveMessages $false |
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