Microsoft Outlook Blocking All Email from Tutanota.com Domain as Spam

Not really true. Many spams (at least in the past) used to include unsubscribe link, either for faked-legal-compliance, to give some illusion of legitimacy of the mail/originating company to the recipient, and/or to track who is actually receiving them.

But if you landed in a mailing list, there are quite high changes that the unsubscribe link is legit.

I'm very surprised to see you are being downvoted, I was convinced everybody is doing that. Spam is spam, period. Asking me go click on a link that leads somewhere is just a waste of my time - and there are still a few culprits out there who instead of unsubscribing me straight away demand that I log in to "manage my notification preferences"!

You're absolutely incorrect about this. What you're saying may have been true a long time ago but it's 100% wrong now. In 2023/2024 you should click unsubscribe links.

No matter how spammy a sender is, an unsubscribe click is a big signal that they don't want to contact that email account again. It takes time and money to warm up a domain, prepare it for outbound email, and keep it from being blacklisted when you're sending out a high volume of mail. The days where someone can just spin up an email server in a couple of minutes and blast hundreds of thousands of people with spam are over. If you don't manage your reputation you'll get blacklisted in a matter of hours. The #1 way as a mailer to manage your reputation is to respect unsubscribe requests.

Yes, clicking the unsubscribe link indicates that there's a real human checking the mailbox. But data resellers have many ways to verify the validity of a mailbox that are more effective than this one. And unlike this one, they don't indicate that the person dislikes receiving unsolicited email. So very few data resellers use unsubscribe clicks as a way to verify email validity, because if they do they'll be polluting their product with the emails of people who are likely to get pissed off by unsolicited mail, report it and get a customer's domain blacklisted. If the data reseller is selling "verified" data that is getting his customers blacklisted - he won't be in business for much longer.

It's worth pointing out that not all unsolicited mail is illegal. There are exceptions carved out in US CAN-SPAM and in other jurisdictions. If you're a business in the US the law is basically that people can send you unsolicited marketing emails whether you like it or not, as long as they provide an unsubscribe link and respect your request if you click it. To not use the mechanism that is explicitly required by the law for your protection is shortsighted.

> as it is scamming, spoofing and innocuous unsolicited marketing

Those are all spam. Especially unsolicited marketing. Fuck everyone who sends that, and I hope they get banned from whatever provider they use and it kills their company. I always report all of those even with an unsubscribe link, as it’s not as if I can trust them not to use "unsubscribe" as a "send more spam" signal, they’ve already proven themselves untrustworthy by not using double-opt-in.

Though with some providers even "mark as spam" seems to be able to leak your email as they send reports which contain the message-id. Good in our case as we don’t want to spam anyone and can then blacklist the address, but bad in case you report evil spammers.

Recently, I managed to get my personal mail server working and delivering to Outlook.

Of all the major mail providers, I found getting my mails to Outlook the hardest. Gmail played nice once I setup DKIM, DMARC, SPF, MTA-STS, rDNS and a couple more things that I forgot setup exactly the way they like it.

Outlook was harder though. I had to send a series of mails spread over multiple days to people who had Outlook accounts and get them to both mark it as not spam and reply to the mail until it eventually started working.

It's been a couple of months, not sure if it still works though. Hope it does.