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"SIP/2.0 504 Cannot connect to gateway. Socket error: TimedOut" error message when a PSTN call is routed to a Mediation server in Lync Server 2010

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Consider the following scenario:
  • You have a Microsoft Lync Server 2010 environment that has more than one Mediation server and a Public Switched Telephone Network (PSTN) gateway deployed. The Mediation servers are configured to use dual Network Adapters.
  • A Mediation server cannot connect to the PSTN gateway because of a network issue that is specific to the Mediation server.
  • You call a PSTN number by using Lync 2010.
  • The call is routed to the Mediation server.
In this scenario, the Outbound Route application in Lync Server 2010 does not route the calls to a different Mediation server. Additionally, the Mediation server returns the following error message:

SIP/2.0 504 Cannot connect to gateway. Socket error: TimedOut

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To resolve this issue, install the following cumulative update:

2502810 Description of the cumulative update for Lync Server 2010, Mediation server: April 2011

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Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

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Keywords: kbqfe, kbexpertiseinter, kbsurveynew, kb

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Article Info
Article ID : 2539642
Revision : 1
Created on : 1/7/2017
Published on : 4/20/2011
Exists online : False
Views : 250