Kelly Lester said
1 year, 4 months ago: If you have trouble getting images to show from your own site when you (or others) post your links on your FB wall, enter the URL of the article herehttps://developers.facebook.com/tools/debug. Then try posting again.
The GREAT thing I just discovered is that you can do it for OTHERS. I wanted to post a fab article from someone’s blog on my FB wall and the link (a very photo heavy post) did not show any of those great images 
So I put the URL of the article through the debugger tool above and then tried to post again on Facebook… and it then showed up with an image!
I really don’t understand how this works, but hey – it’s an easy fix. FB Posts without images don’t make much of an impression…
Lots more about this here: http://ansonalex.com/troubleshooting/fix-articles-linked-on-facebook-dont-display-thumbnails-images/
