Question : What does QoS do and is it necessary?

The event log contains this warning: This host can not be ACS since the Active Directory has not been properly configured via the QoS ACS management console.  Please configure the subnets via the QoS ACS management console.

This machine is a 2000 server that is only used for some older student applications.  Our PDC is a 2008 server and our SDC is a 2003 server.

The other Event Warning is:
QoS RSVP has failed to find any interfaces with traffic control enabled.  Install QoS traffic control services via network and dial-up connections.

Can I just uninstall the  QoS Admission Control Service on this machine or is it still being used in some way?

Most answers I've seen on this issue I think assume that the server has more functions or has more of a role in the domain...

thank you for your help...

Answer : What does QoS do and is it necessary?

I would imagine that there is a global qos ACS management donsole that wants to configure the remote server's qos settings.

Yes, I would uninstall QoS Admission Control Service.