Could be a couple of things that I can think of right now. I tried to hit it directly and I couldn't. The site (or even that particular page) could be offline right now. It might come back in a while.
The other is that some sites really don't allow you to reference image on them from other sites, like you are referencing that image from the DIS board site. That is why it is sometimes easier to get your own site here on the DIS and copy picture to your site that you want to display here.