From: Randem on
If windows complains that files are corrupted then you need to do two
things:

1 - Use the Windows CD to do an Over the top Install. Meaning a repair, not
a console repair but the second repair option if it shows. If it does not
show when it asks you if you want to install Windows QUIT. You will do a NEW
installation if you continue and lose your data.

2 - Use a disk testing utility such as Western Digitals WinDlg to test the
disk for bad sectors. If the program find some it can correct them but if it
finds too many you need a new disk.

Either way you should be able to extract your data or part of it from the
drive that is failing or cannot boot.

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