Topic Last Modified: 2011-04-12

For Microsoft Lync 2010 and Microsoft Lync 2010 Attendant clients that run on the Windows Server 2003 or Windows XP operating system, you cannot use policy-based Quality of Service (QoS).

For QoS to work on the client, the QoS Packet Scheduler must be running on the client computer, and Windows domain policies must allow the computer to use QoS services. For details on Windows Server 2003, see Install QoS Packet Scheduler at For details on Windows XP, see QoS Packet Scheduler at

To enable QoS on Windows Server 2003 or Windows XP

  1. Log on to the computer as a member of the Administrators group.

  2. Start the Lync Server Management Shell: Click Start, click All Programs, click Microsoft Lync Server 2010, and then click Lync Server Management Shell.

  3. At a command prompt, type the following command, and then press Enter:

    Copy Code
    Set-CsMediaConfiguration -EnableQoS $true
  4. Use Group Policy to set Differentiated Services Code Point (DSCP) values that mark the IP packets if you need values other than the defaults to match your environment for Guaranteed service type packets (used for audio) and Controlled load service type packets (used for video). By default, the following settings are applied when you enable QoS:



The client must be stopped and restarted for the change to take effect.