Error 1004 - Thumbnails not working

Hi. Today there was a problem with thumbnails, not being able to view them. On more than a few thumbnails today were not displayed on the page and when clicked on I got a resolution error # 1004. An explanation implies the site has been blocked????
Any idea whats going on and if it can be corrected?

Hello,
Are there any you can show us?

Hmm. I just had to approve this, my own post.