[jabader]

From MS's website:

This issue may occur if one or more of the following conditions are true:

• The basic input/output system (BIOS) does not detect the hard disk.
• The hard disk is damaged.
• Sector 0 of the physical hard disk drive has an incorrect or malformed master boot record (MBR).
  
  Note Some third-party programs or disk corruption can damage an MBR.
• An incompatible partition is marked as Active.
• A partition that contains the MBR is no longer active.

Contact your hardware manufacturer

Your best bet may be to contact the manufacturer of your computer or your hard disk. The manufacturer may have a utility that you can use to perform a more detailed scan for damaged areas of the disk and help verify the correct BIOS settings. However, be aware that the damage to your hard disk may be serious. Sometimes this means that your only solution is to replace your hard disk.



Advanced troubleshooting

Method 1: Verify the BIOS settings

Verify the computer's BIOS settings to make sure that BIOS lists and recognizes the hard disk. See the computer documentation or contact the hardware manufacturer for information about how to verify the BIOS settings.

After you verify that the computer's BIOS detects the hard disk, restart the computer, and then test to determine whether the issue is resolved. If the issue is not resolved, or if the computer's BIOS cannot detect the hard disk, you may have issues with your hardware. Contact the hardware manufacturer to inquire about how to resolve this issue. You may have to replace the hard disk.

Method 2: Use Recovery Console

Use the fixmbr command in the Windows XP Recovery Console to repair the MBR of the startup partition.

Warning This command can damage your partition table if a virus is present or if a hardware problem exists. If you use this command, you may create inaccessible partitions. We recommend that you run antivirus software before you use this command. We also recommend that you backup your data before you use this command. If the fixmbr command detects an invalid or non-standard partition table signature, the fixmbr command prompts you for permission before rewriting the MBR. The fixmbr command is supported only on x86-based computers.