Hi!
I have now tested ARC signing of messages a bit more and have found (I think) all settings so that it works in that it generates the signed headers that ARC is. But the signature is not accepted; gmail says "body hash mismatch" and hotmail says "arc=fail (47)". I have set the following settings under the [ARC] section. I have tried both with the sig_headers set as displayed below and with it commented to lean against the defaults. I use the same key and selector as for DKIM-signing with the server's domain. The DKIM-signature is accepted. Is there any known issues with ARC that I should be aware of? I run the latest release of mailman (3.3.0 of core) on Python 3.7.6 and I use postfix as MTA.
enabled: yes privkey: <my key path> selector: <my selector> domain: <my server's domain>
dmarc: yes dkim: yes authserv_id: <my server's domain> trusted_authserv_ids: <my hosted domains>
#sig_headers: From, Sender, Reply-To, Subject, Date, Message-ID, To, Cc, MIME-Version, Content-Type, Content-Transfer-Encoding, Content-ID, Content-Description, Resent-Date, Resent-From, Resent-Sender, Resent-To, Resent-Cc, Resent-Message-ID, In-Reply-To, References, List-Id, List-Help, List-Unsubscribe, List-Subscribe, List-Post, List-Owner, List-Archive
I hope that this is something simple that I have forgot.
Cheers // David