if you have your Window XP CD then it should be fairly simply to re-install it, if you go into add/remove programs and into the windows components part, if you uninstall the games (under accessories) and then re-install them then it should re-install Spider Solitaire as well.
edit: damn SonicSam got in there first. they should both work lol, his is easier though. if one doesnt work then try the other
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