Banner images in HTML block

How do I get Dolphin to display images from a remote server?

Images from three different affiliates are not shown when linked from their servers, but display fine if linked from an image saved to my server.

I see both images.

 Thanks for the feedback, TravelNotes. I don't know why the remote served images won't show on my system to verify, but at least I now know they display as they should to visitors.