I was wondering why postfix sends error 450 instead of 550 if the mailserver reports that the user is unknown.
postfix/smtpd[16033]: NOQUEUE: reject: RCPT from srvxxx.sysproserver.de[78.138.89.]: 450 4.1.1 <
falscheAdresse@yyy.de>: Recipient address rejected: undeliverable address: host 192.168.1.11[192.168.1.11] said: 550 Address "<
falscheAdresse@yyy.de>" not known here. (in reply to RCPT TO command); from=<absender@.de> to=<
falscheAdresse@yyy.de> proto=ESMTP
It turns out that this behavior is from an very old postfix version and changed in Postfix Version 2.5. Newest stable Version of postfix ist 2.8.4, but on my endian is postfix version
2.3.3 installed. (checked with postconf mail_version on shell)
Now I wounder, why there is such an stale version of postfix (from August 2006 I guess) running on endian V2.4.1 community?
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