This site (http://www.webtree.ca/windowsxp/repair_xp.htm) gives you a variety of solutions for a wayward XP OS. A stab at fixboot/fixmbr might be the first attempt to revive XP, if your HP supplied cd allows, then a Repair install. Note that your data on the drive is at risk and a good backup was never more important then now.
Have a Hewlett Packard Pavillion running XP (I think). When I turn the power on I get the message "Operating System not found", and I can't get past it. What should I do?

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