If you are unable to boot up your Windows XP PC (XP Home or XP Professional), it may be because the boot sector has become corrupted (yet the operating system and data may still be OK). If that is the problem, then this boot disk will enable your PC to ignore the hard disk boot sector, and instead use the boot sector on this boot floppy in order to still boot successfully into Windows XP.
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Start the System Restore tool at a command prompt
1. Restart your computer, and then press F8 during the initial startup to start your computer in Safe Mode with a command prompt.
For additional information about the Safe mode with a command prompt, click the following article number to view the article in the Microsoft Knowledge Base:
315222 A description of the Safe mode boot options in Windows XP
2. Log on to your computer with an administrator account or with an account that has administrator credentials.
3. Type the following command at a command prompt, and then press ENTER:
4. Follow the instructions that appear on the screen to restore your computer to an earlier state.