I give up, it worked now it’s stoped

Hi guys,

I hope someone can help me. I started a weblog, it was succesfully. Now after a few weeks it just stopped working. When I surf to http://www.nickx.be/osxapps/ it wil show nothing. When I surf to the admin and then chooise few site the site IS displaying and working. What could this be.

Not logged in site is not showing
When going to admin and then viewing site is showing.

help is much appriciate !! thank you!!!

Nick

PS: I have tried several different themes. There are no difference.