GMail
Your email@example.com email account can be added to an existing gmail account using the following steps.
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Within the GMail App, tap on your account icon
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Scroll to the end of the list and tap "Add another account"
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Add an IMAP account
email@example.com
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Enter your new email address
email@example.com********mail.emessage.email
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The default port and security type are fine
email@example.com********mail.emessage.email
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The port and security type have changed from the default
Jane Doe
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And you are done.