[Gmail] Email was not sent due to an error in Email configuration.
This tutorial is for companies that are using Google Mail for their Outgoing SMTP mail settings.
Error:
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These steps should be taken to both diagnose and resolve the issue:
Make sure you followed the correct setup procedures.
Navigate to Settings -> Email. Be sure that if you are utilizing SSL port 465 that you have prefixed ssl:// before Gmail's hostname.
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Enable logging;
Look for any timeout entries. They would appear as: SMTP -> ERROR: Failed to connect to server: Connection timed out (110)
Verify that port 465 is open outbound on your firewall.If these steps do not address your issue, please submit a ticket.
Error:
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These steps should be taken to both diagnose and resolve the issue:
Make sure you followed the correct setup procedures.
Navigate to Settings -> Email. Be sure that if you are utilizing SSL port 465 that you have prefixed ssl:// before Gmail's hostname.

Enable logging;
Look for any timeout entries. They would appear as: SMTP -> ERROR: Failed to connect to server: Connection timed out (110)
Verify that port 465 is open outbound on your firewall.If these steps do not address your issue, please submit a ticket.
Updated on: 23/02/2023
Thank you!