If so boot from it - goto the recovery console and type
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chkdsk /r
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This will check your hard disk for errors.
The type
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sfc /scannow
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this will restore the file if it is corrupt.
If the 2 above dont work then boot to the CD and select "repair" by typing R
Let me know how you go
Peter
Please help! Windows XP on my Compaq laptop. I get Stop: c000021a {fatal sys error} Windows process terminated status 0xc00000000 ox00000000. I tried starting in safe mode, last known good configuration, reboot and I get the same message.

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