Post not displaying!!

Hello,

I have created a custom post type in which i display portfolio items. But everytime i go to preview changes it shows an empty page. I also created a page template in which i query the custom post type. the posts show but once i click on the permalink it shows an empty page again. I have tried to go into the permalink settings and resave the options but it still will not work. I should mention that my entire site is running in a sub folder on my server. I also created a single.php for the custom post type and it still will not display. I would appreciate any help thank you.