I finally found my answer. The path to nph-email.cgi was wrong in links.cfg. I must have forgotten to change it when I moved my Links site to it's own domain. Anyone experiencing this problem should check that path.
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Will
Webmaster
FishHoo! Search index for Fishermen
www.fishhoo.com
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Will
Webmaster
FishHoo! Search index for Fishermen
www.fishhoo.com