Next, you can try to repair Windows XP using the following steps:
1 Start the computer from Windows XP installation disc.
For that you need to make sure that the CD drive is selected as the first boot device.
You can set that by going into BIOS setup by pressing F2 OR
press F12 during system startup and select CD drive from the boot options
2 You will get the following messege
Press any key to boot from CD....
Press Enter here
3 The Windows XP installation process will start
4 On the Welcome to Setup page, press Enter (To setup Windows XP now). Do not press R here
as it will start the recovery console.
5 Accept the license agreement by pressing F8
6 The setup will be able to find your Windows Installation and will give you the option to repair the same
7 Press R now
8 Follow the rest of the onscreen prompts
The following link will provide a step by step guidehttp://www.windowsreinstall.com/winxphome/installxpcdrepair/indexfullpage.htm
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