Symptoms

Consider the following scenario:

  • A user makes a Public Switched Telephone Network (PSTN) call In a Microsoft Lync Server 2010 environment..

  • The PSTN call is routed from a Mediation server to a gateway that is disconnected from the Mediation server.

In this scenario, the Mediation server rejects the call. Additionally, the Mediation server returns the following error message:

SIP/2.0 503 Service Unavailable

Note This error message only contains an "ms-trunking-peer-state" header. However, it should also contain an "ms-trunking-peer" header. 

Resolution

To resolve this issue, install the following cumulative update:

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

Status

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

Facebook LinkedIn Email
SUBSCRIBE RSS FEEDS

Need more help?

Want more options?

Discover Community

Explore subscription benefits, browse training courses, learn how to secure your device, and more.

Microsoft 365 subscription benefits

Microsoft 365 training

Microsoft security

Accessibility center

Communities help you ask and answer questions, give feedback, and hear from experts with rich knowledge.

Ask the Microsoft Community

Microsoft Tech Community

Windows Insiders

Microsoft 365 Insiders