DocFraggle
I know it. Almost 😉 Not the exact minute I ran it.
DocFraggle
The mail was definetly not correctly signed. It was signed with my dkim key (which was the correct one for the senderheader). But I think the provider checked against the from header. And since this was unchanged and not from my domain there was a mismatch, of course. Mails wich originated on my server have a valid signature. In this case there is no problem.
ETNyx
I’m aware of that and I’d also contacted the provider.
Today they confirmed that it was definitely a problem with the dkim signature. Due to the fact that the network segment where my server is located does not have a high reputation, they only accepted mails with a valid dkim signature. Strangely enough, all mails from the mail queue were still delivered yesterday evening (long before I setup SRS).
I have now setup SRS in mailcow so that I won’t have so many problems with forwarding in future. At least I hope this will help.
But the thread here can be set to solved for all I care? The only question is: can I do this myself or does an admin have to do it?
And maybe as an addition: I had the feeling, that all of this only was a problem when the original sender hasn’t signed the original message.
I’m far away of being a postfix/dkim/… expert. So that could be complete rubbish. But some mails went through without a murmur. However, these were all correctly signed by the original sender.