- 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.