Find out the name of the NetBus-server (which is most often Patch.exe). Run RegEdit.exe and lookup the registry-key \HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run. From that key you should be able to sort out the NetBus server program (again, most often Patch) from others.
When you've found the suspicous entry, do a file-search for "[Name of the NetBus-server].exe" on your system. Finally run "[Name of NetBus-server].exe /remove". If you've run the NetBus server you should see that it just starts and ends quickly without any user-interaction. That's just fine.
An easier approach, could be to use the NetBus-client (NetBus.exe) yourself, connect to localhost, choose "Server admin" and click on the "Remove server" button.