Cause:
Even when Network Load Balancing (NLB) is not currently installed, some NLB registry keys may be present in the registry. Microsoft has identified this as a problem in Windows 2000 Advanced server. The recommended solution also resolves the issue in Windows 2003.

Fix:
Start > Run > Regedit {enter}
Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WLBS
Select the Group key it will be set to PNP_TDI delete this entry so there is no value

If the above doesn’t work on its own then delete the following keys
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Eventlog\System\WLBS
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WLBS

Comments:
References

http://seer.support.veritas.com/docs/263037.htm
http://support.microsoft.com/?kbid=268437