Managing personal Outlook.com account settings, security, and privacy
Hi Martin Brunning,
I understand why you would want to remove an address you do not recognize. However, the Email accounts page in your screenshot does not by itself confirm whether the Outlook.com address is an alias or a separate Microsoft account.
Please sign in to Manage how you sign in to Microsoft and check whether the unwanted address appears under Account aliases. If it does, it is an alias connected to the same Microsoft account rather than a separate mailbox.
Before removing it, make sure another address is set as the primary alias and that you can still use that address to sign in. Please also note that removing an @outlook.com alias permanently deletes that email address, so it cannot be restored or added to another Microsoft account later.
If the address is not listed under Account aliases, could you clarify whether you recognize creating it and what happens when you select Manage beside it? Thank you so much for your understanding.
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