In our service center before installing any sp2 or sp3 we run to fix all the problems that seen over and over again, also seen this work in Vista.
start subinacl /subkeyreg HKEY_LOCAL_MACHINE /grant=administrators=f /grant=system=f
start subinacl /subkeyreg HKEY_CURRENT_USER /grant=administrators=f /grant=system=f
start subinacl /subkeyreg HKEY_CLASSES_ROOT /grant=administrators=f /grant=system=f
start subinacl /subdirectories %SystemDrive% /grant=administrators=f /grant=system=f
start subinacl /subdirectories %windir%\*.* /grant=administrators=f /grant=system=f
start secedit /configure /cfg %windir%\repair\secsetup.inf /db secsetup.sdb /verbose
Hope this helps some one;