Cannot add external pstn user to internal conference after conference starts. ID:404 RRS feed

  • Question

  • Dear all,

    We're using OCS 2007 R2 on Server 2008, we have standard edition servers installed for front end, an edge server and a mediation server. All users are using the R2 client, we do not have pbx integration.

    Our mediation server has only one nic.

    We have enterprise voice enabled with a sip trunk from interouteone, it seems to work very well after some initial issues with a Checkpoint firewalls interpretation of the call setup procedure. We can dial out and voice quality is great. Our problems come when establishing conferences between pc audio clients and pstn clients.

    If i call a PSTN user first, i can subsequently succesfully, add internal, communicator/pc audio clients to a conference with the pstn user.

    If i call a communicator/pc audio client first i cannot subsequently add a pstn user to the conference, when i do this i receive "An error occurred during the call. More Details (ID:404) in communicator

    If i snoop the S4 logs on the mediation server I see

    SIP/2.0 404 Not Found both in and outbound.


    Ms-diagnostics: 10404;source="mymediationserver.atmycompany.net";reason="Gateway returned a SIP failure code";component="MediationServer";SipResponseCode="404";SipResponseText="Not Found";GatewayFqdn="89.202.*.*"

    My interpretation of this is that this is an error from my SIP trunk providers gateway? However i find that difficult to believe as they provide this service to hundreds of companies and i expect the issue is more down to my misconfiguration.....

    Is this due to a difference in the way conference calls are dialled as compared to normal calls? Perhaps a number translation issue?

    If i examine my communicator logs i see this when i try to add the external pstn user to the conference already in progress: SIP/2.0 481 Call Leg/Transaction Does Not Exist

    Any guidance appreciated.


    Friday, January 8, 2010 7:22 AM

All replies

  • Can you verify there is a valid route for the number you are dialing.


    Also, can you verify that your mediation server has a location profile assigned to it, should be under the properties of the mediation server.



    Randy Wintle |MVP:Communications Server, MCTS: UC Voice Specialization | Winxnet Inc
    Wednesday, November 3, 2010 1:51 PM
  • "If i call a PSTN user first, i can subsequently succesfully, add internal, communicator/pc audio clients to a conference with the pstn user. "

    Can you add another PSTN number in this scenario?

    Technical Specialist Microsoft OCS/UC - http://www.uwictpartner.be
    Monday, November 8, 2010 9:46 AM
  • Jim,


    I've seen this with certain sip trunking providers when the calling number is being passed as a sip uri instead of a tel uri, which is consistent with your scenario. In the event that you start an internal conference, then attempt to add an external (PSTN) participant, Lync may be sending the sip uri of the conference initiator. In the case when you start a PSTN call first, just the line uri is sent as the calling number. Will you please trace the logs for calling number? You may have to rewrite the calling number in certain scenarios.


    • Edited by LK23 Tuesday, December 7, 2010 5:17 AM Updated small font size
    Monday, December 6, 2010 6:30 PM