New posts in smtp-headers

Handling badly folded long Return-Path header gracefully

Postfix does not add to: header for outgoing mail

How to configure Postfix to only send out emails with a certain header?

Is there a legitimate reason to use an encoded word in any header other than the subject?

Prepend X-header to all relayed messages in Postfix

With valid SPF my mail header becomes huge -> high spamassasin score

How to modify Receive header in Postfix

Why is sendmail adding an extra carriage return in headers?

Mail Enable email headers when sending emails via ASP.NET

Can't find received_header_text in exim.config file

what addresses are in the first "received:" entry in email header

Why does my server hostname appear in Exim email headers sent from a different domain?

Postfix: selecting relay host based on From: mail header rather than envelope sender

Why don't my domain's messages to a google group get their headers rewritten so DMARC can pass?

Forwarding email with postfix via AWS SES

"Delivered-To" Header in Exchange

postfix - different header checks for incoming and outgoing mail

How to block SendGrid spam with sendmail?

Scrub header for internal servers in Postfix?

Postfix "header_checks" is insane for me to accomplish [duplicate]