Question regarding Posts not Showing Under Category

I installed a different theme Gazette and my posts don’t show under the category section. If I switch back to a default theme they will show. I tried updating the permalinks to default then back to no avail..

http://stockhowto.net if you notice under any category it just returns a blank page.

Anyone have any ideas? I’ve been reading and trying to change all sorts of functions.php copied my pages.php and index.php in the theme to mimic each other, fresh install.. I’ve tried everything haha