Managing personal Outlook.com account settings, security, and privacy
The old Xbox Live Family email domains were retired years ago, and if a third-party account (such as Ubisoft) is still configured to send recovery emails to that retired address, Microsoft generally cannot restore access to that mailbox.
Your best option is to contact Ubisoft Support directly and explain that the recovery email is being sent to a discontinued Xbox Live Family address that can no longer receive mail. Be prepared to prove ownership of the Ubisoft account using information such as:
- Your Xbox gamertag
- Linked Xbox account details
- Previous Ubisoft usernames
- Purchase history, game ownership, or transaction IDs
- Any other account verification information Ubisoft requests
Since the recovery process is controlled by Ubisoft, only Ubisoft can update or remove the obsolete email address on their account system.
You can contact Ubisoft Support here: Ubisoft Support.