ich wollte eine Mail versenden und bekam folgende Rückmeldung:

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 send mail to postmaster.

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

The mail system

<gewinnspiel@schlagerparadies.de>: host mx1b.fritz-services.com[136.243.66.27]
said: 554 The IP Address of the sender (194.25.134.18) was found in a DNS
blacklist database and was therefore refused. (in reply to RCPT TO command)

wie komme ich da wieder runter und wie bekomme ich raus ob ich noch woanders auf einer Blackliste stehe. Warum stehe ich auf einer Blackliste?