I’ve been receiving a lot of spam in my inbox, which shouldn’t happen because an address has to be put into my address book to go there; otherwise it goes to the Suspect folder. The headers all have Return-Path: <Return@linkedin[dot]com>. (Dot replace by [dot] so it doesn’t link here.) The addresses in the ‘From:’ line are all different.
Question: If the ‘From:’ address is not in my address book, and the LinkedIn address is not in my address book, why is spam going into my inbox?
What email client are you using? How did you set up the requirement that an address has to be in your address book or else it goes to a Suspect folder?
Earthlink. (More accurately, netcom; which became Earthlink.) I set it up by choosing this option:
Suspect Email Blocking — Highest Protection
Messages from unknown senders (those not in your Address Book) are redirected to your Suspect Email folder. This setting includes Known spam Blocking.
I suppose the simplest cause might be the email blocking feature is not working properly.
I was trying to think of some scenario where the From header might be malformed in such a way as to not be processed - does the email show the ‘from’ address when you view it in the client (i.e. not the raw headers, but rendered)?