Some QoS Group Policy settings are not retained after you restart a client computer that is running Windows Vista or Windows Server 2008
On a client computer that is running Windows Vista or Windows Server 2008, you apply some Quality of Services (QoS) Group Policy settings under the following subsection:
Local Computer Policy\Computer Configuration\Administrative Templates\Network\QoS Packet Scheduler
When you log on to the client computer, you see the Group Policy settings are applied correctly. However, after you restart the client computer, the Group Policy settings are no longer applied.
For example, you enable the Group Policy setting “Guaranteed service type.” You specify a custom Layer-3 Differentiated Services Code Point (DSCP) value for packets with the “Guaranteed service type.” After you restart the client computer, the custom Quality of Service (QoS) DSCP settings in the Group Policy are not retained. In this scenario, the default value for “Guaranteed service type” is used by the operating system after the computer is restarted.
This problem occurs whether you apply the Group Policy settings by using the local policy, or by using Group Policy objects in an Active Directory domain.
This problem also occurs on a client computer that is running Windows XP or Windows Server 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
972878 The “Guaranteed service type” Group Policy setting returns to the default value after you restart a client computer that is running Windows XP or Windows Server 2003
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB973779.