|A few things can cause this problem.|
1) there is a CD or Floppy left in the drive when the system boots in which case it needs to be removed from the drive and then restart your computer.
2) The Master Boot Record or Boot.ini files have become corrupted and the system cannot find a bootable device to start windows...You can boot to the installation CD and choose to go to repair console and repair either one of the options.
3) your harddrive has just died on you and will need to be replaced. Sometimes the files can be retrieved by a recovery application and sometimes they cannot....depends on how bad the drive was damaged.
In either one of these cases...this is perfect example on whay backing up to a different media on a regular basis is so important
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