Managing personal Outlook.com account settings, security, and privacy
I understand how confusing it is to be caught between your AOL sign-in, Outlook account, and Microsoft Authenticator.
Your AOL address may be the sign-in name for the Microsoft account that holds your Microsoft 365 subscription. If your existing Outlook.com address shows as already taken, it is likely already connected to a separate Microsoft account and cannot be added as an alias to the AOL-based account.
Please sign in to the Microsoft account associated with your AOL address, open Your info > Manage how you sign in to Microsoft, then select Add email and create a new Outlook.com address as an alias. Do not remove your AOL address, as it remains connected to your subscription.
Once the new alias has been created, try adding the account to Outlook on your iPhone again. If verification is required, ensure that the same AOL-based personal Microsoft account is registered in Microsoft Authenticator.
Please feel free to let me know if you have any further updates, thanks.
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