Halifax

This is a DOS command I assume (which would make if fdisk /mbr, since the DOS command format has no /mbr switch, IIRC)? The Master Boot Record holds the information the BIOS needs to figure out what partition to boot from and possibly how to go about booting it (it's been a long time since I researched the MBR). If the MBR is blank, you'd most likely get an "Operating system Not Found" or "Inaccessible boot Device" error because the BIOS doesn't know what to do with the drive. If you're lucky the BIOS might search the partitions in logical order for a partition labeled as "boot", but probably not. I guess it really depends on which OS you reformat the MBR from. Using Fdisk or the Windows Recovery Command Console (use command FixMBR) will reformat it to boot windows, and will get rid of GRUB or LILO (Linux boot loader programs). Like I said earlier, if it's blank, probably nothing would boot. And if this is just for homework, try reading the book. I don't mean to sound snappy or mean or anything, but it really does help sometimes. ^__^ If all else fails, ask Google and you'd probably get a quicker answer.