Clicking on thumbprints on web sites

I have just experienced a strange thing which I am very puzzled about. On a certain web site I clicked the small photograph fully expecting it to show up bigger which it did not. Instead, it just showed an imagine number but no picture. I right clicked on the area near the number and clicked on SHOW PICTURE but no picture came. There were several on this particular web page and on the same site but on another page of the same site I did the same thing and clicked on the image and it showed the bigger size of the picture. Now if there was something wrong with my settings on my computer surely I would not have been able to see the pictures on the different page of the same web site. I have tried so hard to sort this out myself but to no avail. Regards Syd