Microsoft Lync and Skype for Business have a rich set of .NET APIs which make it easy to extend the platform and integrate it with other applications. This blog helps explain how to use those APIs.

Sending calls to a voice mail box in UCMA without a missed call notification

Posted: March 31st, 2014 | Author: | Filed under: UCMA 4.0 | Tags: , , | 4 Comments »

A while back, I wrote a post on how to call an Exchange UM voice mail box directly. The trouble with the approach described in that post is that it generates a missed call notification in the Exchange inbox of the recipient. A colleague of mine discovered a way to nix this missed call notification, and I thought I would share it.

You can get a SIP URI that goes directly to a user’s voice mail box by appending ;opaque=app:voicemail to the end of that user’s address of record. For instance, if the user has the SIP URI, you can get their voice mail box by calling;opaque=app:voicemail. However, this will lead to a missed call notification.

If you instead call;opaque=app:voicemail;local-resource-path=voicememo, you will get the user’s voice mail box but there will be no missed call notification.

4 Comments on “Sending calls to a voice mail box in UCMA without a missed call notification”

  1. 1 Awil said at 10:30 pm on September 12th, 2014:


    How does ucma applications handle presence for users homed to an SBS? Since the ucma app is registered against the main pool and relys on presence to to determine if the user is available to bring into a conference call.

  2. 2 Michael said at 11:18 am on September 19th, 2014:

    They handle presence for those users just as they would for any other users. Unless there is a connectivity failure between sites, the UCMA application will receive presence updates from the users via the pool it is registered against.

  3. 3 Mauro said at 9:56 am on September 30th, 2014:

    i use an application to parse all SIP messages (MSPL + dispatcherHandler in c#) but if the receiver of the message has the voice mail enabled, the message is blocked with the error 486.
    Have you ever experienced this problem?

    I forward the message using these commands:

    eventArgs.Request.SimpleProxy = true;
    eventArgs.ServerTransaction.EnableForking = false;

    ClientTransaction ct = eventArgs.ServerTransaction.CreateBranch();

    Thank you

  4. 4 Rin said at 4:25 am on December 28th, 2015:

    Mauro ,

Leave a Reply

  • Note: Comment moderation is in use because of excessive spam. Your comment may not appear immediately.