I checked ISPC 18.104.22.168 and this user exist! Yet I get this in the logfiles. Authtest works correct as well as some postmap tests, It seems the issue is with the relay=maildrop permissions? In the code part I highlited the error by adding spaces around the line. Code: # cat /var/log/syslog |grep 441D01A06148 Aug 27 15:46:52 artemis postfix/smtpd: 441D01A06148: client=localhost[127.0.0.1] Aug 27 15:46:52 artemis postfix/cleanup: 441D01A06148: message-id=<firstname.lastname@example.org> Aug 27 15:46:52 artemis postfix/qmgr: 441D01A06148: from=<[email protected][email protected][email protected][email protected][email protected] Were is this permission problem? How could it change - this was an perfectly working installation. maybe caused by an apt-get upgrade?