I sent an email to firstname.lastname@example.org, my old email at Microsoft.
Can you receive this mail?
This was my email alias many years ago.
Jian Shuo Wang
mail.microsoft.com rejected your message to the following email addresses:
mail.microsoft.com gave this error:
The email address you entered couldn’t be found. Please check the recipient’s email address and try to resend the message. If the problem continues, please contact your helpdesk.
Diagnostic information for administrators:
Generating server: BY2FFO11HUB004.mail.protection.outlook.com
Bingo! My email address is still not occupied by someone else. Just for the record, I checked just because we were at a Microsoft gather, and some conversation inspired my curiosity.