Dear HN,due to some successful phishing attempts at my scientific research organization with over 2k personnel, we've been blacklisted by Microsoft, which causes valid e-mails to their domains being rejected. This is a substantial problem, because it prevents a lot of scientists (and administration) from being able to efficiently communicate over the mailing-lists, and the like.Our ticket system is still been flooded about this and although it is not my responsibility, I wanted to ask: why is it so easy for a three-letter domain, that's been online since the dawn of the Internet to get blacklisted so easily? Even a simple WHOIS request yields a "Changed" record stating 2017. Is the rejection list based on IPs? Is there anything preventing the usage of a more differentiating algorythm?The respective requests to fix the problem have been sent, but it's been at least a week already and the havoc is real.Please feel free to share your thoughts. Thank you!