* Michael Ludwig: > So any help is greatly appreciated.
I doubt that Postfix is the culprit. I ran into similar issues a while ago: E-Mail sent by me which included German umlauts did not arrive with a valid DKIM signature. I thought that disabling the 8BITMIME extension in Postfix was a possible solution, but that did not make a difference. After fruitless experiments, I found that Thunderbird was (at least partly) to blame. Only after setting "mail.strictly_mime=true" via TB's config editor did I no longer experience DKIM signature breakage. My point is that it is not trivial to figure out where your problem originates. If you find a solution, I would be very interested hearing about it. -Ralph
