Telekom is a bunch of strange folks. I lately was not able to send mails, from my private mail servrr to my fathers telekom mail. After investigation I found out my server got blocked. After a decade of working. I mailed them, and they told me to register my mailserver with them. I shall tell them what mails I will send from there and about what content. I couldn’t believe my eyes. Sure, thats how mail was supposed to work. Register with every mail server in the world, before you can send mail.

Their mail excerpt: This system has not sent any e-mail to our customers for a long time. For security reasons our systems will only accept e-mails from such IP addresses after a check of setup and information about these systems.

Please give us details about this system and the company using it, tell us all about the sending domain, what type of e-mail will be sent and especially if you or your customer want to send newsletter give us detailed information on how recipients e-mail addresses had been acquired. Who in person is responsible for e-mail sent from this system (MTA)?

Please be advised that only technically proper configured and very well maintained systems are qualified for a reset of reputation and please see our FAQ section 4.1 (Requirements for smooth access to our e-mail exchanges <https://postmaster.t-online.de/index.en.html#t4.1>):

"There must be a domain and website with direct contact information easily deducible from the delivering IP's hostname (FQDN)."

That policy of theirs has existed for a long time now. It's a really odd one at that.

They also don't enforce DMARC, nor do DKIM. It's stuck nearly four decades in the past.

Well, I don't know if that is better or worse than my experience with Comcast. They will usually unblock my emails within a day of my sending an unblock request, no questions asked... and then block me again after a few days, with no explanation as to why. I've had this IP for years, I have spf, dkim, and dmarc all property configured, I'm not on any blocklists, and I only send a very small volume of personal emails from the server.

I think this is standard. It applies to domains as well. I experienced government services blocks as well -- they send me an email, yet block my reply. I complain every time and rarely does anyone care, the support person does not escalate, so my email remains blocked, sometimes I'm told system is working as configured, completely ignoring that I am a real person and system is hostile towards me.

It's just general fragility of tech and lack of care from the creators/maintainers. These systems are steampunk, fragile contraptions that no one cares to actually make human friendly or are built on crappy foundations.

but the fun thing about them is, they allow you to impersonate any mail address you want with their smtp server.

Aka, when you are a customer of them you get a @t-online.de address and login data for their smtp server.

You can just login into that server and set the From: Header to anything, they don't check.

At least they respond quickly to such inquiries. I have given up on T-Online Mail. I refuse to follow ridiculous rules like these.

They just want to make sure you're not a spammer.

Been there, done that. After a bit of back and forth, Telekom basically recommended that I go and use one of the big SMTP servers and stop bothering them. While I hated myself for doing it, I eventually switched to Gmail for peace of mind.

Well, we have to "register" every new IP or new mail server with them as well. It's annoying and a weird system, but they respond quickly and it's just one todo we have to think about.

Does anyone self host email anymore successfully? I'm honestly asking. I would like to but it seems like a full time job trying to keep it running. Are there halfway solutions where maybe you own the service and domain and it runs somewhere trusted?

> about what content

Ask ChatGPT to generate you a very long very graphic story about how much you'd like to fuck a dog and your father is the only person who understands your desires and you want to discuss this with him via email. While fucking dogs is illegal in Germany, talking about it is (probably) not. Make the guy who asked the question regret doing it.