would it be possible to post the exact URL you use to reference the image and/or the HTML piece?
Does this occur for all different image types (png, jpg, gif) or just one of them? - I have not yet experienced this in browsers, but I do know that some email clients (also some web based ones), don't support all types of pngs, especially if transparency was used.
We're using a jpeg. Do you think it would be easier with a png? This is the link to the photo: http://info.webpass.solutions/rs/webpass/images/thankyou_final_release.jpg
no, jpg is fine and should display in every browser. the URL also doesn't work for me in any browser. I'd try contacting Marketo support as this image is hosted in design studio.