The local device is already in use!

Hi,
I changed the DNS servers IP addresses (Primary and
Secondary)in the Windows 2000 server. Since then my
Windows 2000 Professional and Windows XP Pro machines
cannot connect to network resources. It shows that its
logged on but none of my network drives or resources are
accessible and it give me this error on Win XP Pro
machine "The local device is already in use" when I try
to open mt network drives. I have Stopped and restarted
the DNS and Wins services on the server and rebooted it
but it still does'nt work. Please help me!

Shawn