Links give 404 error--SportsPress

All of my "category" links are ending up as 404 errors, even when accessed through the correct web address. Help!!

Hi! Please give us a link to your website.

I'm also having the same problem but just with IE. Firefox and Chrome work fine.
http://www.fracaoinvestimentos.com.br/site/
Click on any meny item and you'll see a page not found error on IE.

I was thinking on buying this theme but gave up on the idea after this.