First you have to check the Windows Services and make sure that all CiscoWorks processes are stopped.
Set them all to Manual and reboot the server.
Once you log back in, delete all CiscoWorks files and folders (usually CSCOpx folder)
Now, go to the registry: Start -> Run -> Regedit
Go to hkey_local_machine\software\cisco and remove the resource manager folder
Reboot, and that should do it