Ich erhalte die folgende Mail:

421 Too many messages (1.5.6.3) on 2018/12/10 18:58:41 GMT from

    un-validated IP address: 194.25.134.18. Please add a SPF record for the

    domain t-online.de to your DNS or ask your Broadband Provider / Domain

    Registrar to do this, we will be unable to deliver email until this is done

    due to the volume of email being sent from this IP address. Guide for bulk

    senders www.bt.com/bulksender (in reply to MAIL FROM command)

oder

This is the mail system at host mailout06.t-online.de.

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