Norton won't allow pics to open - within an email

On 3 computers that I have Norton installed on, on emails with an chart or graph within the body of the email, won't open. All that shows up is a little "x"
 in a small black box. Even right clicking on it, it won't open the graph. I have Kaspersky on a couple computers and those computers allow the email to come through just fine as well as my smart phone (which has Norton on it)...I get the email just fine. It has to be a setting or some I'm assuming!

What do I have to change.