Getting 404 error when I click on a subcategory link

I have a category (two actually) with multiple sub-categories. The main link goes to a single category page where it shows all the sub-category links. When I click on the sub-category link it takes me to a "404 Sorry but we couldn't find the blog entry that you are looking for" error page. This happens on both category pages. I posted to one of the sub-categories, clicked and it still took me to the 404 page.

All categories are published.

my two category links from the main menu:
Vote Left>Candidate Profiles
Blogging the Left>Blogger Community

Thanks