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（2） In the Pop-Up, choose an account to sign in with.
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（3）Enable your account.
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Tips：When you have multiple accounts linked to your Gmail email address and set up a default send email address, the system will also follow your Gmail settings.
When you change the default sending email, please click “Refresh” on the system configuration page to sync your settings, otherwise it may not work.
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Note: The sending limits, such as the number of emails sent per day and the number of recipients per email, are subjected to your SMTP server.
And to use office365 mail, you need to add the office365 mail to an administrator email.
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