diverse.direct have put a big banner on their website asking to allow emails from that domain name to be received (for some like hotmail altogether, not just into a spam folder) for several large email hosters.
Because email hosters refuse to admit new domain names are trustworthy and are probably spam.
This is how the real world functions too. Everyone doesn't trust you by default and unless you have powerful connections you can't really change that. And the internet was meant to change that.
If having own domain, you could supply spf entry in domain dns settings. This tells, which mail servers are permitted to send in behalf of your domain, even if using external mail like google etc.
Without such things one easily can fake, that spam is what you sent out.
Nobody wants to get responsible for those spammers.
It's poor that people cheat for profit much as possible and actions against are required. Egoism is shitty but capitalistic.
@hamjb Yes, but I'm talking about actually hosting your own email service, rather than using $bigco$'s email service for which you need to pay.
You can setup DKIM and DMARC too and that should theoretically boost your domain's trustworthiness to some hosters, but definitely not to hotmail or anything microsoft. They operate on a whitelist-basis.
It speaks volumes that $bigco$'s emails don't even use DKIM or DMARC but just their reputation.
But spf you did?
It works before emails are exchanged, due to dns level and might be first step.
If domain is rejected before smtp, anything within smtp security is useless
@hamjb Not me, just in general people who host.
SPF usage even for clueless naive people who host their own emails is very widespread.
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