TLS Connection Error SendMail tls: first record does not look like a TLS handshake

Troubleshooting
7

Hi, @djangofan

Let us troubleshoot this based on the information provided in the official SMTP Email Setup:

  • Set SMTP Username to [YOUR_SMTP_USERNAME]
  • Set SMTP Password to [YOUR_SMTP_PASSWORD]
  • Set SMTP Server to email-smtp.us-east-1.amazonaws.com
  • Set SMTP Port to 465
  • Set Connection Security to TLS

With reference to the following error that you are getting:

Let us take a look at your Mattermost email settings. Can you please run the following command on the terminal and provide the result with the sensitive information such as password redacted:

cat /opt/mattermost/config/config.json | grep -A29 "EmailSettings"

Also, are you getting those errors you listed when you click on the Test Connection button based on the combination of SMTP Server Port and Connection Security?