a customer had the problem that he couldn’t install the Windows Vista Service Pack 2 on his Laptop. Service Pack 1 seems to be installed, but the Service Pack 2 Setup says it isn’t.
I processed a query by using the WMI Command line tool and filtered for Service pack 1 (Hotfixnumber KB936330).
wmic qfe|findstr /I 936330
But in the list of installed hotfixes KB936330 is not listed. WinVer.exe reports a Vista with Service Pack 1 installed.