I have translated "bounce_template_file" to Danish, and besides the localized letters, it works fine (the English part is still present in the error).
In /etc/postfix/main.cf I have set delay_warning_time = 4 bounce_template_file = /etc/postfix/bounce.cf When I run "postconf -b /etc/postfix/bounce.cf" it works great - the Danish letters are shown in my terminal, and postconf gives no errors. However, when Postfix returns a answer after 4 hours plus some, the localized letters are gone. For example, this English line we all know: "This is the mail system at host myhost." I have translated it to this: "Det her mailsystemet på værten mydomain." (the first localized Danish letter is å, and it's suppose to look like this: https://en.wikipedia.org/wiki/%C3%85 ) Instead it looks like this: "Det her mailsystemet pÃ¥ værten mydomain." In /etc/postfix/bounce.cf I have tried ISO-8859-1 and ISO-8859-4 as charset at the beginning of all 4 parts. The header of the delay_template part looks like this: delay_template = <<EOF Charset: ISO-8859-1 From: MAILER-DAEMON (Mail Delivery System) Subject: Forsinket email Postmaster-Subject: Postmaster Warning: Delayed Mail I guess the problem is this advice from bounce(5) "Specify an appropriate superset of US-ASCII." I mean, not the advice itself, but more the fact that I can't find such a list. Does anyone know what subset to use for Danish?