What is the reason for not displaying the email?

Question

Layout of letters

Why is the email not displayed, but only the text of the layout itself is displayed instead of the letter? Where to look for the reason?
I did a test mailing and such a jamb, I think it makes no sense to throw the whole layout here, maybe someone came across, or just understands what it could be from?

Answer 1

www.flashissue.com/blog/how-to-paste-html-into-gmail