This issue occurs in the following scenario:
- You define more than one Session Initiation Protocol (SIP) domains in a Microsoft Lync Server environment.
- You deploy both Lync Server 2010 front-end pools and Lync Server 2013 front-end pools in the environment.
- You create a response group in a Lync Server 2013 front-end pool.
- You select the Enable queue time-out check box for the response group, and then you click Forward to telephone number to forward a call that times out to a Public Switched Telephone Network (PSTN) number.
- A user is homed in a Lync Server 2010 Front-End pool.
- The user calls the response group.