Pentium 4 2.8Ghz Abit IS7 mobo Lite On CD-RW Sapphire ATI Radeon 9000 Pro Antec Tru Power Hitachi Deskstar HDD, 80GB SATA This problem originated after I defragged my main hard drive, or after I added a new Maxtor One Touch External HDD, 250 GB at around the same day. When next time I re-booted the computer, I received the "ntldr missing, press control+alt+delete to restart". After researching the problem and trying all the fixes I could find on the internet without success, I decided I would reformat and reinstall Windows XP since I had my important docs and files on CD-RW. I ensured that I could boot up with CD-ROM in BIOS. In fact, I checked to make sure all my BIOS settings were accurate. When I try to reinstall Windows XP using the Windows XP Home Edition Setup exactly as described in Windows Reinstall.com, I get to the page that lists the existing partitions and unpartitioned space on the computer. C: (NTFS)is there with 78529 MB listed as free space, plus 8 MB unpartitioned space. It also says "Unknown disc", and "this drive does not contain a disc." Huh??? When I press enter to continue with the install, it says: "To install Windows XP on the partition you selected, Setup must write some startup files to the following disk...Unknown Disk. However, this disc does not contain an XP compatible partition." It then asks me to return to the partition selection screen and create a windows compatible partition on the unknown disk. I have deleted and created umpteen new partitions, and have tried everything I can think of to get past this hurdle, with no luck. Why does it state "unknown disk"? Is this where the root of the problem is, and if so, how do I fix it. Thanks for any help.

Tim Leinweber, SWAG, sounds like somehow, another partition got created during the format process. Dunno if it'll do you any good, but my inclination would be to reformat/reinstall again. Seems to me you have little to lose (just time) and maybe you have been victimized by a glitch? HTH. Ed in Texas.

Thanks for the reply. It will not let me do that. I cannot get past this screen: "To install Windows XP on the partition you selected, Setup must write some startup files to the following disk: Unknown Disk However, this disk does not contain a Windows XP-compatible partition. To continue installing Windows XP, return to the partition selection screen and create a Windows XP-compatible partition on the disk above. If there is no free space on the disk, delete an existing partition, and then create a new one. To return to the partition selection screen, press enter." When I do what it asks, it just repeats all over again. I have tried F6 to reinstall SATA drivers (which I never had to do before and everything worked fine), and have tried manually reformatting the hard drive from the recovery console first, which I should not have had to do either. Also, the external drive is not presently connected.