I came across an error today when trieing to install WSUS 3 on one of our servers, it appeared to get to the end of the installation process and then failed with the error.
‘Windows Server Update Services 3.0 SP2 could not install WSUSService and the performance counters. For more information, see the Setup logs’
To rebuild the performance counters goto a command prompt and run
C:\windows\system32> lodctr /R