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New Member

Blank messages - Unity 4.05 UM/ TSP 8.13/ E2K3 / CM 4.1

Note from customer - does anyone have any feedback before I start digging?

I have identified an issue that seems to be more and more prevalent as we increase the number of users that have Unified Messaging. Several users appear to receive, what they perceive as, "blank" voicemails. These voicemails appear within a users Inbox, the From field states that the message is from Unity Messaging System and the Subject line states 'Message from xxxxx' (the xxxxx is normally the ext number of that users voicemail).

Under most circumstances, I have found that the majority of users who have complained about receiving blank voicemails have received a message similar to the one I described above. However, without physically seeing the format of the message within Outlook we can not be sure this is the case.

Through some investigation of my own, I have found that these blank voicemail occur due to the following:

- User has phone forwarded directly to voicemail


- Users phone is down or disconnected, not allowing it to receive calls


- Any other scenario that would cause the phone NOT to ring when receiving a call


- User has playback device within Outlook set to 'Phone'

Under the above circumstances, a user who attempts to listen to a voicemail will see the voicemail begin to play, however there is no device "playing" the voicemail. It appears that the voicemail system picks up the call and consequently records an empty voicemail, which in turn is sent back to the user.

To my knowledge, this appears to be a glitch in the logical flow of voicemail from Outlook to the playback device (phone). Under normal circumstances, a user who attempts to listen to voicemail through Outlook with the phone as the playback device does not receive this blank voicemail. After 4 rings, the system recognizes that the user is not answering and completes one more attempt before notifying the user that no one has answered the device.

It appears that the same should occur when a phone does NOT ring; it should notify the user that the device is not being answered, or something of that sort. Please investigate further to determine if this is indeed a glitch with the Unity Messaging System.

New Member

Re: Blank messages - Unity 4.05 UM/ TSP 8.13/ E2K3 / CM 4.1

have the same problem, they were saying it is random and will try your methods to see if they replicate.

The system I am working on is ver 4.0(3)

TSP is also 8.1(3)

I have a copy of two recordings, both are about 26- 28 seconds in length and if you turn up volume all the way can hear some static. Same issue when playing it from the actual phone as well

Cisco Employee

Re: Blank messages - Unity 4.05 UM/ TSP 8.13/ E2K3 / CM 4.1

Do calls to Unity use g.711, g.729 or both? With g.711 Unity can perform silence detection which should prevent it from recording blank messages.

When you say "xxxxx is normally the ext number of that users voicemail" do you mean it is the subscriber's primary DTMF accessID? Or is it the DN of one of the Unity ports? I would expect the latter because it sounds like you have an outbound call from Unity (TRaP) that gets forwarded immediately back to the subscriber's greeting. If this is the case, then you may be able to block this with the following...

1) dedicate some out-bound only ports on Unity. i.e. remove the Answer Calls function for the ports in UTIM and remove the ports from the phone systems hunt

2) enter valid extension numbers for the ports in UTIM

With this, Unity will reject any inbound calls whose callerID matches that of a dedicted dial-out port.