If you are unable to display email images using Gmail the problem is more likely related to your browser settings.
let ‘s say you receive one of your newsletter something like
if you click on “always displays from …” nothing happens this post is for you:
Tools - Internet Options -> Security(tab) -> Custom Level
Locate “Display Mixed Content”
I have mine on Prompt so I will get prompted the next time i click on “always display images from…” something like
Click No if you want to see the images or Yes if you want to keep hiding them