Considering there is no such thing as Invision 3515b... there's an "a", but not a "b"... he may have gotten a hacked script. If he means Invision 2b3515 (with or without the "a" at the end), then that wouldn't be a hacked script as long as it's from an official source.
I've never heard anyone having that much trouble with Invision and Nortons (usually just during install if anything.. .and that depends on the virus definitions file being used). So, in either case, it does sound like he's perhaps infected by something. Who knows.
