I have installed a 40 GB hard drive as a slave to the original 3 GB that came with my 'hand me down' Compaq Deskpro 4000. (The other specifications were unavailable besides my motherboard's being dated 1997-1998.) I already have a dual-boot with Windows NT 4.0 and Windows XP on the original disk. My intent was to add the second disk for strictly storage purposes. My problem emerges in two places: first, I get an error message 1791 that reads disk 1 error(disk 1 is the newly installed disk) then I'm prompted to press f1 to boot. I boot up fine, go into disk management within XP and make a primary partition of about 10 GB, after which I'm prompted to format. Everything seems fine until the formatting reaches 100% completed and I'm told in an error message that the format couldn't be completed. Please, can someone assist?