I too Have Vista on My Notbook but I never saw any corrupt DL issue's, But then again I turned off that security service I think it's called UAD or UAC or something like that. Anyway I also recall back in the day I had a corrupt DL issue & I ended up looking in the event log only to see a whole lot of bad block alert/errors (Bad C:\drive) anyway not to tell You guys stuff You already know, but You might check Your drives integrity with a tool like HD Tune

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