The fixboot command is a Recovery Console command that writes a new boot sector to the system partition you specify.
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This command is only available through the Recovery Console in Windows 2000 and Windows XP.
drive = This is the drive that a boot sector will be written to, replacing the system partition you are currently logged into. If no drive is specified, the boot sector will be written to the system partition you are currently logged into.
Below is an example of how to use the fixboot command.