I'm sending an email to let's say email@example.com and Hotmail returns error email that the email was not delivered to firstname.lastname@example.org Same as when the account does not exist.
So I have tried to register it and it says that I cannot register that account.
Why I cannot register it? Is there any waiting period?
(Note that the account name that I'm trying to resiter is not someting like email@example.com or firstname.lastname@example.org)