If it's a bios problem, why not have him update his bios?
Format C of course will delete your entire drive, but it might work (just make a full backup first). I'm sure he was kidding though... The sledgehammer is a good solution, but unfortunately it's a one shot deal.
Still, if you use Win9x at least, it's a good general rule of thumb to reformat your system ever 6-9 months or so, to keep things running smoothly.
[ July 18, 2001: Message edited by: Kurgan ]