Unlike Windows 7 and Windows Vista, Windows XP does not utilise BOOTMGR. The equivalent function in Windows XP is called NTLDR (an abbreviation for NT Loader).
There are few different ways that the "NTLDR is missing" error may present itself, with the first listing being one of the most common:
NTLDR is missing
Press any key to restart
NTLDR is missing
Press Ctrl Alt Del to restart
Boot: Couldn't find NTLDR
Please insert another disk
The NTLDR is missing error displays very shortly after your computer is first started, immediately after the Power On Self Test (POST) is complete. At this point in the boot process, Windows XP has only just initially started to load.
There are a number of possible causes for NTLDR errors, including the most common "NTLDR is missing" error message.
The most common reason for this error is when your PC is trying to boot from a hard drive or flash drive that is not properly configured to be booted from; in other words, it's trying to boot from a non-bootable source. This also would apply to media on an optical drive, floppy drive or flash drive that you're trying to boot from.
Other possible causes include corrupt and misconfigured files, hard drive and operating system upgrade issues, corrupt hard drive sectors, an outdated BIOS, and damaged or loose cables.
The NTLDR error could be a one off problem and may not present itself again when you restart your PC.
Often times, the "NTLDR is Missing" error will appear if your computer is trying to boot to a non-bootable floppy disk, CD/DVD, or external hard drive or flash drive.
If you find that this is the cause of your issue and it's happening regularly, you might want to consider changing the boot order in BIOS so the hard drive is listed as the first boot device. As your PC boots up it will show you the key to press to enter the BIOS. Typically the key to use will be Delete or Esc, but there are other possibilities including F1, F2 and F10. It depends on the make and model of you BIOS program.
Check the hard drive and other drive settings in BIOS and ensure they are correct. The BIOS configuration tells the computer how to use a drive so incorrect settings can cause problems, including NTLDR errors.
There's usually an Auto setting in BIOS for hard disk and optical drive configurations which is usually a fairly safe bet.
Restore the NTLDR and ntdetect.com files from the Windows XP CD. Restoring these two important system files from the original Windows XP CD may do the trick.
Boot off the Windows XP CD and start the install.
Select language, time and currency and Click Next to proceed further.
On the next screen, select “Repair your computer”.
Enter the Windows XP Recovery Console.
When you reach the command prompt, type the following two commands, pressing Enter after each one:
copy d:\i386\ntldr c:\
copy d:\i386\ntdetect.com c:\
In the command listed above, d represents the drive letter assigned to the optical drive that your Windows XP CD is currently in. While this is most often d, your system could assign a different letter. Also, c:\ represents the root folder of the partition that Windows XP is currently installed on. Again, this is most often the case but your system could be different.
If you're prompted to overwrite either of the two files, press Y.
Take out the Windows XP CD, type exit and then press Enter to restart your PC.
Assuming that missing or corrupt versions of the NTLDR and/or Ntdetect.com files were your only issues, Windows XP should now start normally.
NTLDR error messages may also appear if the master boot record is corrupt.
Enter the Windows XP Recovery Console.
When you reach the command prompt, type the following command, and then press Enter:
This instruction should repair the boot record by replacing the missing files.
Even though a repair installation does not alter any programs or data, other than Windows XP itself you should still make a backup of all your important files in case something goes seriously wrong.
The Repair Installation should replace any missing or corrupt Windows XP files and this is how to proceed with this.
Place the Windows XP setup CD in your CD/DVD drive and restart your PC. This will start the install routine.
When the 'Press any key to boot from CD' message is shown on your screen, press a key to start your computer from the Windows XP CD.
Press ENTER when you see the message 'To setup Windows XP now', and then press ENTER again on the 'Welcome to Setup' screen.
Do not choose the option to press R to use the Recovery Console.
In the Windows XP Licensing Agreement, press F8 to agree to the license agreement.
Make sure that your current installation of Windows XP is selected in the box, and then press R to repair Windows XP.
Follow the instructions on the screen to complete Setup.
NTLDR error messages could be caused by loose or malfunctioning IDE cables so try replacing the IDE cable, especially if you suspect that it might be faulty.
Write a new partition to the Windows XP system partition and make it bootable. If the the original partition boot sector has become corrupt or isn't properly configured, you may receive the "NTLDR is Missing" error. Use a tool like Paragon's Partition Manager or EASEUS Partition Master to create the new partition and make it active.
Performing a full installation of Windows XP should fix almost anything, as long as it's not a hardware related problem.
This type of installation will completely remove Windows from your computer and install it again from scratch. While this will almost certainly resolve any NTLDR errors, it's a time consuming process due to the fact that all of your files and data must be backed up and then later restored. You will also have reinstall all your programs.
If, for some reason, you can't gain access to your files to back them up, beware that you will lose them all if you continue with a clean installation of Windows XP.
Occasionally, an outdated BIOS version can cause the "NTLDR is Missing" error. So updating your PC's BIOS might fix the problem.
Finally, if all else fails, try replacing your hard drive and then perform a new installation of the Windows XP.
Note: NTLDR Errors only apply to the Windows XP Operating System, including Windows XP Professional and Windows XP Home Edition. For Windows 7 and Vista see the article The 'BOOTMGR is missing' error.
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