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                   The mail system

<m.guenter@t-online.de>: host mx01.t-online.de[194.25.134.72] refused to talk
    to me: 450 4.7.1 [EAB] 554 IP=23.83.222.30 - A problem occurred. (Ask your
    postmaster for help or to contact tosa@rx.t-online.de to clarify.) (BL)
Reporting-MTA: dns; relay.mailchannels.net
X-Postfix-Queue-ID: 2BC8C5C8003
X-Postfix-Sender: rfc822; matthias@junker-immobilien.de
Arrival-Date: Fri, 22 Sep 2017 17:58:19 +0000 (UTC)

Final-Recipient: rfc822; m.guenter@t-online.de
Original-Recipient: rfc822;m.guenter@t-online.de
Action: failed
Status: 4.7.1
Remote-MTA: dns; mx01.t-online.de
Diagnostic-Code: smtp; 450 4.7.1 [EAB] 554 IP=3D23.83.222.30 - A problem
    occurred. (Ask your postmaster for help or to contact tosa@rx.t-onlin=
e.de
    to clarify.) (BL)
Betreff    test to t
Von    matthias@junker-immobilien.de
An    m.guenter@t-online.de
Datum    Fr 13:58