My son has bought a new hard disk to replace a faulty one (he has an old PC to play around with, but it's very important to him!) When he starts it up he gets the message: "Disk boot failure, insert system disk and press enter". However, when he inserts the XP disk into the CD drive, the "disk boot failure..." message comes up again. He has organized the boot order on the BIOS with the CD drive as No.1 and the new hard disk as No.2 He has checked the cables (the BIOS appears to 'see' all the drives). There are two hard disks and two CD drives, but he has tried both of the CD drives. The BIOS gives a message along the lines of "ultra 100 BIOS cannot be read because there are no drives attached" - but it skips past this message and ends up at the "disk boot failure...." Before he changed the hard drive, the XP disk would read, but now it doesn't even if he puts the old drive back in place (he gets the "disk boot failure..." message. The PC is about 6 or 7 years old. Anyway, if anyone could suggest a next step, he'd be so grateful.