There are many causes to the error and some of the more common ones are that
1. Computer is booting from a non-bootable source.
2. Computer hard disk drive is not properly setup in BIOS.
3. You have a Corrupt NTLDR and/or NTDETECT.COM file.
4. There is a Misconfiguration with the boot.ini file.
Anyhow if you wish to fix the "NTLDR is Missing" error then there are a couple of methods at your disposal. Firstly if you still have your Windows Boot Disk, then you can use that to help you repair the Error, you will simply have to insert the disc run the Recovery Console and enter in a few commands which may cure the problem ( Visit The Link at the bottom which contains the exact procedure and commands to enter).
If you don't have the Windows
CD or lost it then you could create your own NTLDR boot Disk to get back into Windows and then Use windows to fix the boot files on the hard drive. It is a fairly complicated and tedious procedure that requires a lot of trial and error. I would only recommend it for advanced computer users who have considerable technical knowledge about windows and system files. If you would like to give it a try conduct a search on Google "How to create your own NTLDR boot Disk" and you should find a few tutorials that will guide you through the entire process. Just remember nothing is guaranteed and you may not fix your problem, also Unnecessary mishandling of the computer hardware or software could cause serious data loss and make your computer unusable in the future.
The easiest and most effective way to fix the "NTLDR is Missing" error would be to obtain a decent professional software that is specifically designed to cure this problem. These programs will easily help you recover your missing Windows NTLDR File and restore your Computer back to its normal state with the click of a few buttons. It is probably your only safe option if you don't have a Windows
CD and do not wish to re-format your entire hard drive, which you will end up costing you all of your precious data.
So if you are looking for a way to Fix "NTLDR is Missing" error then don't worry there are a few ways you could go about repairing it. If you have the Windows
CD then using the recovery console may get your system back in action, otherwise you could conduct a repair installation of Windows XP and that may fix the problem. If for some reason you don't have your Windows
CD or if it simply didn't fix your NTLDR problem then you can easily fix the problem by using professionally designed third party software. Personally I used the Spotmau Powersuite Program to recover my Missing NTLDR File, all I did was insert the CD, run through a few simple steps, restarted my computer and it was back in action! Therefore if you want to Repair your Missing NTLDR File you can either use your Windows
CD or if you don't have that then grab a good Windows Recovery Program and your Computer will be to normal in no time.
how to fix ntldr is missing