In an earler thread on this topic, OCE_Ady reported back that
<QUOTE>
I've been asked to ask if you're using a mass mailiing product and if you've manually set your public IP for the mail service? Your emails are being sent by a mail port that is not used by us now and is not using the correct MX record.
<UNQUOTE>
I do use a mail forwarding service and I would like to know how to change to the correct port, given that these addresses are not generated by me, and how to change to the correct MX record, also not generated by me.