Article ID: 2517715 - View products that this article applies to.
Consider the following scenario:
ms-trunking-peer-state: downAdditionally, any PSTN calls that you make afterward are rejected.
This issue occurs because an ms-trunking-peer-state: down header is added to all calls after the Mediation server detects lost connection to the PSTN gateway. When the Outbound Route application on Lync Server 2010 receives this header, it assumes that the gateway is offline, and then rejects any calls afterward. Additionally, it does not try to route calls to a different Mediation server.
To resolve this issue, install the following cumulative update:
(http://support.microsoft.com/kb/2502810/ )Description of the cumulative update for Lync Server 2010, Mediation server: April 2011
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.