Hello everybody, I have a question I couldn't find in the search. Maybe someone has a workaround for the problem. Thank you. We have added another domain to an existing Office 365/ Exchange account with created users and groups. So far everything works. For the users I was able to add the new domain to the alias, so that the mails are accepted accordingly. Unfortunately, this is not possible with the created groups, so that the Exchange rejects the mails to the group address with the new domain name. But I can't create a mailbox with the domain, because there will be an SMTP error message.