==== REQUIRED BASIC INFO OF YOUR IREDMAIL SERVER ====
- iRedMail version (check /etc/iredmail-release): v1.2.1
- Deployed with iRedMail Easy or the downloadable installer? manual
- Linux/BSD distribution name and version: Debian 10
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MariaDB
- Web server (Apache or Nginx): NGINX
- Manage mail accounts with iRedAdmin-Pro? -
- [IMPORTANT] Related original log or error message is required if you're experiencing an issue.
====

For years I have been getting angry on a regular basis about Micro$oft's / Outlook's / Hotmail's / live.com's shi**y and incomprehensible blacklist approach. They are just blocking whole IP ranges without ever naming a reason. I have seen so many admins getting frustrating, because they spent days to make everything compliant with all MTA relevant RFC policies - including me. It just so poor how Micro$h*t tries to become the holy grail of mail exchange policy pioneers, while they are actually one of the worst.

After so many discussions on their support channel with no result whatsoever I have decided to come up with a better idea. It's not the solution that changes their behaviour, but it is the solution that turns away all the work and lost time related to anti-spam and gives it back to them.

So:
My plan is to block all mails send from outlook, hotmail, live and office users and return just the same stupid mailer daemon report to their users that the return to our users.
The idea is that their users shall then contact their support and deal with them instead of outsourcing all the work from Micro$h*t to us mail admins and raping our time schedules wiht useless "support" conversations.

This is a generic amiler daemon report example from Micro$h*t:
--
The mail system
<username@live.de>: host eur.olc.protection.outlook.com[*IPaddress*] said:
    550 5.7.1 Unfortunately, messages from [*IPaddress*] weren't sent. Please
    contact your Internet service provider since part of their network is on
    our block list (*somenumber*). You can also refer your provider to
    http://mail.live.com/mail/troubleshooting.aspx#errors.
    [*.*.prod.protection.outlook.com] (in reply to MAIL
    FROM command)
--

Now, before you come up with "Hey, that's not the right thing to do here" let me say: I know. And I don't care. I want Microsoft to deal with it, not me.

So, my idea is to set up a mailer daemon report with the same text and a "support" page somewhere in the net, where Microsoft support then can go click themselves through the same idiotic "support request form". They will then get the same useless generic answer and we tell them to please comply with RFC soandso and enlist in some kind of program. And so on... I think everyonoe gets the idea now, right? It's about turning things around 180 degrees.

So who's in?

First step would be to enlist all IPs of outlook, hotmail, live etc and block them.
Then create a mailer daemon report template.
Then create the "support" website and so on.

What do you think?