This is the mail system at Centrum Holdings

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please contact your system administrator.

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                  The mail system


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Reporting-MTA: dns; gmmr1.centrum.cz
X-Postfix-Queue-ID: 1E956800E807
X-Postfix-Sender: rfc822; nedbalek.j@centrum.cz
Arrival-Date: Thu, 12 Dec 2019 12:15:24 +0100 (CET)

Final-Recipient: rfc822; plesnik@spedos.cz
Original-Recipient: rfc822;plesnik@spedos.cz
Action: failed
Status: 5.7.1
Remote-MTA: dns; posta.spedos.cz
Diagnostic-Code: smtp; 554 5.7.1 Service unavailable; Client host [46.255.225.252] blocked using zen.spamhaus.org;  https://www.spamhaus.org/sbl/query/SBL468702

Final-Recipient: rfc822; vana@spedos.cz
Original-Recipient: rfc822;vana@spedos.cz
Action: failed
Status: 5.7.1
Remote-MTA: dns; posta.spedos.cz
Diagnostic-Code: smtp; 554 5.7.1 Service unavailable; Client host [46.255.225.252] blocked using zen.spamhaus.org;  https://www.spamhaus.org/sbl/query/SBL468702


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