@kev Well done Kev. I can say though that a lot of Email users are broken!
I run my own Email services for my domain. All properly done with DKIM, DMARC, SPF and RDNS (I'm a good citizen).
My wife uses our system and deals with many less savvy using live.com and outlook.com addresses.
For no good reason much of her Email lands in their Spam folder. Asked "Can you mark me as a trusted sender?" they say "No, your Email got marked as Spam, it's for you to fix!".
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