I’m resetting this tip from two or so years ago because we have had so many phone calls and email messages about this topic.
Have you ever received an email with "red x’s" in a box or just an empty box in the middle of the email? There are three possible explanations for this phenomenon; either you are reading the message offline, your email program is blocking images from appearing in your email, OR more likely the pictures or graphics that were supposed to be in that message didn’t get sent with the message.
First, a quick background on how pictures work in email messages. Email originated as a text only medium, but in the late 90’s it evolved to the point that it was possible to send embedded pictures, colored text and more with email. This is called Hyper Text Markup Language (HTML) email. In English, that means special computer code to display those pictures and formatted text. Essentially, email has become like mini-web pages. One problem with HTML email is that not all email programs or users can read this type of email…they simply see the plain text devoid of pictures and formatted text.