Ich bekomme seit Wochen immer wieder Emails zu unbekannten Emailadressen als undelivered zugestellt. Was kann ich hier unternehmen?

This is the mail system at host mailout08.t-online.de.

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

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

                   The mail system

<golovinsasha1957@yavdex.ru>: connect to yavdex.ru[194.58.112.174]:25:

    Connection timed out

<media@academy.kremenchug.net>: Host or domain name not found. Name service

    error for name=academy.kremenchug.net type=MX: Host not found, try again