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If you enter any incorrect information you will get an error or fail on the SMTP dashboard page.
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Tips:
This has to be a regular email address, not a group email, it has to accept SMTP Connection to send the emails.
We require SMTP authentication, so a username and IP address is required.
Gmail google tutorial on how to "Turn on Less Secure apps" https://support.google.com/accounts/answer/6010255?hl=en and if you have 2 step authentication, you will need to generate an "App Specific Password" on Gmail https://support.google.com/accounts/answer/185833?hl=en or Apple https://support.apple.com/en-us/HT204397