Hi @Zahidul Haider ,
If you’re referring to Microsoft accounts, once an alias is removed from an account, it cannot be reused. According to Microsoft’s policy, if you remove an alias that’s an email address from a Microsoft account (like @outlook.com, @live.com, @hotmail.com, or @msn.com), it cannot be re-created as a new account or alias. This means it won’t be available again as an alias or new account to you or anyone else at a later time.
However, if the alias was for a different domain (not @outlook.com, @live.com, @hotmail.com, or @msn.com), the rules might be different. For instance, after removing a proxy/alias email address for a user mailbox in Office 365, you can reuse the same name to set up a shared mailbox immediately.
Please note that these policies can vary depending on the email service provider.
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