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If using Gmail, or Google as your SMTP provider, please select TLS for security and use port 587. Note also that by default Google may not allow you to send from an address set in your email templates if it is different than the user you authenticate with via SMTP.
In order to send from a different address, you must create an alias
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and allow your email address to do so.
- First create the Alias, you can do that by following the steps at this link: https://support.google.com/a/answer/33327?hl=en
- Once you've created the Alias go to Settings > Accounts, where it says "Send mail as:"
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- click "Add another email address."
- A new window will appear, enter your name and the alias you created and check the box that says "Treat as an alias."
Note: If you have configured various email addresses in your Email Templates. You have to create each alias in Gmail and allow it.