Not just Microsoft/Ionus
Several of our customers have had problems reaching us recently, we use Deutsche Telekom as our mail provider. They have blacklisted a lot of data centres and ISPs.
Usually we can provide them with the server address of the customer and they are whitelisted again. But one recently was served through a major Mexican data centre and when we provided DT with the details, they wrote back that until the customer's provider got its house in order and provided them with specific information how they would stop a spam wave in the future, they would not whitelist the hoster or any of their customers.
Biting the hand that feeds IT
