http://www.palmersoft.co.uk/support/xp/corruptreg.asp

A corrupt registry can be one of the hardest things to recover from, not only is it a long winded procedure but it is also reasonably technical. In this article I have tried to provide an easier alternative, however this is not something that should be undertaken lightly. If at anytime you are unsure of anything stop and consult a qualified professional.

Windows XP could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEM

Windows XP could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SOFTWARE

Stop: c0000218 {Registry File Failure} The registry cannot load the hive (file): \SystemRoot\System32\Config\SOFTWARE or its log or alternate

Microsoft have provided a way of recovering from a corrupt registry, their solution is contained in: http://support.microsoft.com/kb/307545/

However if you either do not know the Administrator Password, or cannot load the recovery console, follow the instructions below. ...

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