Hi to all of you, since weeks I'm struggling with this problem, not being able to solve it on my own and I think the last possibility of getting help is to ask you, the experts right here. I set up a mailserver with the help of a howto I found on the net. Mainly everything is okay, mails are received and sending is also possible. Spam is getting sorted out and DKIM, SPF and DMARC is working on the domains I switched to that new mailserver.
A few weeks ago I figured out that there is a problem when a conversation is going on via mail, at some point the postfix changes the content-transfer-encoding from 7bit to quoted-printable. This makes sense, the MTA postfix is doing what it is expected to. I've read about line-lengths, 8bitmime, utf8 and so on. But this behaviour is breaking DKIM signing, as signing with rspamd is done before the encoding conversion. So I hope there is a possibility to get this problem solved with your help. Please forgive me that at this point I did not post any details as I am waiting for you telling me what configs, logs, snippets, headers and so on you need to have in order to be able to help. What I know is that rspamd is called via the milter functionality of postfix. But I didn't find any ressources on the net on how to change the order, so that rspamd dkim signing comes last. This seems to be important in the master.cf as that must be the point where the smtps-session is controlled. But I can't see anything where it calls the milter, so that is why I have no clue where to begin searching. So any help is greatly appreciated. Best regards, Michael
