It is a method and procedure to change the administrator email address of WordPress itself.
General Settings → Administrator Email Address
WordPress itself has an email address for administrators, separate from the email addresses registered by users.
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This is how to change the “administrator email address”.
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Set your new email address
First, set a new email address in the administrator email address section.
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Scroll to the bottom and press the Save Changes button.
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You will then receive a notification of the change at the email address of your new admin email address .
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[site name] email address for new administrator
An e-mail will be sent to the e-mail address for the new administrator, “[site name] new administrator’s e-mail address”.
Click the “If this is correct, click the link below to change it.” link.
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Since it will be the login screen of WordPress, log in with the administrator username and password.
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The admin email address has been changed!
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summary
You can change the administrator email address by following the steps above.
Please refer to it.