Re: Service Pack update, now machine won't...
Try booting to Last Known Good Configuration by hitting F8 during startup, it'll be one of the options listed. If that doesn't work, do you have the XP disk still? You can try doing a repair install if you do.
1. Insert the XP disk and boot off it
2. Press Enter to start installing XP, do NOT press R
3. Press F8 when prompted to agree to the EULA
4. Windows will then search for existing windows installations. It should find yours and ask you whether you want to repair or continue installation. Choose the repair option.
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