Receiving backscatter emails from one of my Verizon email addresses. It is from firstname.lastname@example.org and the subject is "Delivery Notification: Delivery has failed". I blacklisted this in Apple Mail to deposit into a "spam" folder but it is coming into it at a rate of 200+ per hour. Can I determine the original ISP from the long headers in the email and contact Verizon to get it blocked? The email is in German. Any help would be greatly appreciated. This started this morning.