1. Go “START”, “RUN” type “CMD” Press “OK” or Boot PC into “safe mode with command prompt”
2. Type sfc /scannow /f (note:- space after sfc)
3. Windows file protection will check your files. Follow any prompts; you may be required to use your XP CD.
4. Re-boot your PC
A windows repair will replace the files witch infact is needed files. Last nite I had a machine with a NTLDR missing. I didnt want to doa win_repair because I was looking for a 'workaround' just to get into windows. i was forced to do the win_repair at the end.
NOTE: when you're done with the windows repair, open explorer>tools>folder options>view. Tick the checkbox that ive circuled in red in the image thats attached. Reason being so that you dont delete the neseccery files again by accident at a later stage :)
Mmm... these are the two that you should [must] have: ntdetect.com
Copy them in from another sys. If your sys is still running don't shut it down until you have replaced them into the root of your System Drive. [usually C:\]