Type cmd into the search bar of the Start Menu and right-click on the cmd.exe result that is returned to access the Run as Administrator option. Provided you are using an administrative account, as required by Windows XP as well, SFC should then work as expected.
I am so confused with the authority premise in Vista!!!!!!!!!!
Running SFC in XP was so easy and now I'm told I need clearance to run a command in my own machine..and try as I might...I CANNNOT run SFC in Vista.............No wonder my prime machine is XP