Symptoms
You develop an application to examine the chat messages in each chat room by using Microsoft Lync Server 2010 Group Chat SDK. In this application, you use the ChatRoomSession.EndQueryChatHistory method. If there are no chat messages in the chat room, the EndQueryChatHistory API throws an unhandled exception. This behavior causes the application to crash.
Resolution
To resolve this issue, install the following cumulative update:
2603298 Update package for Lync 2010 Group Chat SDK: December 2011
More Information
For more information about the ChatRoomSession.EndQueryChatHistory method, visit the following Microsoft website:
General information about the ChatRoomSession.EndQueryChatHistory method