I don't get the Email thing anyway.
I had an email server and configured everything by the book. Still some scammer were able to send emails which looked like they came from me, so i got responds back.
If not even this was fixed...
That's what DMARC and DKIM can help with. If you have `p=reject` then anything failing your DKIM check will be rejected by the recipient mail server (if it supports DMARC)