Sending, receiving, and organizing email in Outlook.com
Hi @Zephyr
I understand how concerning this is, especially when you need the old address to receive a password-reset email.
If the removed alias ended ******@outlook.com, @hotmail.com, @live.com, or @msn.com, removing it permanently deletes that email address. Even if you appear to have added the same address again, the original mailbox alias cannot be restored or reused.
If the alias uses another provider, such as Gmail or Yahoo, adding it to your Microsoft account only makes it a sign-in alias. Emails sent to that address will continue going to the mailbox hosted by that provider, not to Outlook.
For the account that requires a password reset, try updating the registered email address or using another recovery method offered by that service.
Please feel free to let me know if you have any further updates, thanks.
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