You deploy the Response Group Service (RGS) in a Microsoft Office Communications Server 2007 R2 environment. Occasionally, RGS agents cannot receive calls until you restart the RGS on all front-end servers. Additionally, the following event is logged on the server that is running the RGS:
Log Name: Office Communications Server Source: OCS Response Group Service Logged: <Date> Event ID: 31017 Task Category: OCS Response Group Service Level: Error Keywords: Classic User: N/A Computer: <Computer name> Description: Unable to subscribe to the agent presence.
Cause: Networking problems with the Front End server or a misconfigured Front End server. Resolution: Verify that you have connectivity with the Front End server.
This issue occurs because Unified Communications Managed API (UCMA) cannot update the presence subscription for all agents after one of the front-end servers is restarted. RGS agents cannot receive calls without the presence status.
To resolve this issue, install the following cumulative update:
2501720 Description of the cumulative update for Office Communications Server 2007 R2, Unified Communications Managed API 2.0 Core Redist 64-bit: March, 2011
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.