Missing NTLDR can be caused by any one of these problems :-
Computer is booting from a non-bootable source.
Computer hard disk drive is not properly setup in BIOS.
Corrupt NTLDR and/or NTDETECT.COM file.
Misconfiguration with the boot.ini file.
Attempting to upgrade from a Windows 95, 98, or ME computer that is using FAT32
New hard disk drive being added.
Corrupt boot sector / master boot record.
Seriously corrupted version of Windows 2000 or Windows XP.
Loose or Faulty IDE/EIDE hard disk drive cable.
Failing to enable USB keyboard support in the BIOS
With Windows XP follow these instructions
Once both of these files have been successfully copied, remove the CD from the computer and reboot.
- Insert the Windows XP bootable CD into the computer.
- When prompted to press any key to boot from the CD, press any key.
- Once in the Windows XP setup menu press the "R" key to repair Windows.
- Log into your Windows installation by pressing the "1" key and pressing enter.
- You will then be prompted for your administrator password, enter that password.
- Copy the below two files to the root directory of the primary hard disk. In the below example we are copying these files from the CD-ROM drive letter, which in this case is "e." This letter may be different on your computer.
copy e:\i386\ntldr c:\
copy e:\i386\ntdetect.com c:\
If this doesn't work, then the last resort is to install Windows again, plus the computers device drivers and your programs.