A Lync 2010 user cannot share his desktop or share an application during a Lync online meeting that contains an OCS 2007 R2 user and a Lync 2010 user

Applies to: Lync Server 2010 Enterprise EditionLync Server 2010 Standard Edition

Symptoms

Consider the following scenario:
  • You are a Microsoft Lync 2010 user. 
  • You create an online meeting, and then you invite an Office Communicator 2007 R2 user and a Lync 2010 user to join the meeting successfully.
  • You try to share your desktop or you try to share an application to these users.
In this scenario, you cannot share your desktop or share an application. Additionally, you receive the following error message:

Screen sharing cannot connect to the server now. Please wait and try again. If this issue continues, contact your support team with this information.

Cause

This issue occurs because of a deadlock in Application Sharing Server (ASMCU). Every time that ASMCU tries to construct a new RtpConference object, the ASMCU blocks are waiting for the platform lock to complete. The platform lock is waiting for the event handler lock to complete, and the event handler lock is waiting for the platform lock to complete. Therefore, a client time-out occurs.

Resolution

To resolve this issue, install the following cumulative updates:  
2449497 Description of the update package for Lync Server 2010, Web Components Server: January 2011
2467776 Description of the update package for Lync Server 2010, Conferencing Server: January 2011

Status

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