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How to Reinstall Outlook Express in Windows XP
Search your hard disk for a file named Msoe50.inf. It should be in your \Windows\Inf folder, although your Windows folder might have a different name. Right click on the Msoe50.inf file and click the Install command. You'll be asked for your Windows XP CD, so make sure you have that handy. Follow the installation routine's instructions and you'll get Outlook Express up and running again.

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