Error 404 when clicking on "glossary item"

Hi There,
I just installed your plugin. I created a couple of Glossaries, then used the shortcode to add it to a page. That works fine. But when I click on a glossary, the post comes up as a “404 page not found”. For example http://www.website.com/glossary/cat, is coming up as page not found, instead of my “cat” entry