have you ever experince this kind of problem?
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when this problem happen your PC cannot log in into WindowsXP. All you have to do is get your WindowsXP installation cd and follow this steps:
1. Boot your computer using that cd
2.At WindowsXp Setup menu , press R (repair windows)
3.You log on to windows installation and ask for admin password. Just type in your admin password and press Enter
4. type these following command :
x:i386ntldr c:
x:i386ntdetect.com c:
5. Above command are copying file from your WindowsXP cd into your drive C:, after that reboot your computer.
x is your CD-ROM / DVD-ROM.
eg.
E:i386ntldr c:
E:i386ntdetect.com c: