The error in Tutanota's screenshot implies that someone has added this domain as some form of AD or organisation instead of a personal email. It's not a "your d

The error in Tutanota's screenshot implies that someone has added this domain as some form of AD or organisation instead of a personal email. It's not a "your domain is banned" message, it's a "contact your tutanota.com organisation's admin to have them create an enterprise 365 account for you"