Gestion des paramètres de compte de Outlook.com personnels, de la sécurité et de la confidentialité
Hi Damien,
I'm Sumit, here to help with your query on the Microsoft Q&A forums.
Apologies for any inconvenience you are experiencing. I am happy to help you today.
Sorry to see you go. May I know why are you closing the account?
The message simply means the account is added as a guest in a Business organisation. You might be able to leave the org using this page:
https://myaccount.microsoft.com/organizations?ref=AccountSettings
I hope you find this information useful. If you have any more questions, don't hesitate to reach out. Otherwise, please take a moment to rate the thread. Wishing you good luck!