|What OS version is the bootdisk? What size is the hard drive? Did it previously work OK in that computer or did you swap it from another one?|
After booting from the bootdisk, type FDISK and enter. Do you get 'error reading fixed disk' or ' no fixed disk present'?
Or do you get the regular fdisk menu? If so, choose option 4 and post back what it says.
Real men don't use AntiVirus; they just reformat