I will try the Postfix built-in header_checks – PREPEND I will also post my results. Thank you for the details.
From: <owner-postfix-us...@postfix.org> on behalf of Wietse Venema <wie...@porcupine.org> Reply-To: Postfix users <postfix-users@postfix.org> Date: Thursday, June 30, 2022 at 09:53 To: Postfix users <postfix-users@postfix.org> Subject: Re: How can I set a "Reply-To" header ? White, Daniel E. (GSFC-770.0)[AEGIS]: I found out how to do it from command line: echo -e "Testing Mail\nThank you" | mailx -v -s "Testing Mail" -S "reply-to=yom...@example.com<mailto:yom...@example.com>" m...@example.com<mailto:m...@example.com><mailto:m...@example.com<mailto:m...@example.com>> This smells like a common webserver problem, where the webserver submits email messages that appear to come from rhe web server's UNIX account (www-ser...@example.com<mailto:www-ser...@example.com>). Adding a Reply-To: header is the WRONG solution for that. Instead, specify the correct envelope sender address: /usr/bin/sendmail -f yom...@example.com<mailto:yom...@example.com> recipient.... If that is not your problem, read on for more. Is there a way to add a 'Reply-To' header from the Postfix configuration ? You can use milter-regex to inspect email and add or change headers. You can use Postfix built-in header_checks to PREPEND a header but that will add the header even if the message already has a Reply-To header. /^From: blah@example\.com/ PREPEND: Reply-To: yom...@example.com<mailto:yom...@example.com> The example needs to be tweaked to the exact form of your message headers. I looked in the documentation but could not find anything about setting such a header, conditionally or otherwise. Yeah. There is nothing about adding REPLY-TO headers. Wietse
