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Troubleshooting failed emails

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TL;DR
  • Authentication errors usually mean a wrong password or an app password is required.
  • Timeouts usually mean the wrong port or the secure option doesn't match the port.
  • Emails in spam usually mean SPF, DKIM or DMARC is missing for your domain.

Authentication failed

Section titled “Authentication failed”
  • Re‑enter the username (usually the full email address) and password.
  • Gmail and many providers need an app password. See Gmail.
  • Microsoft 365 may have SMTP AUTH turned off. See Outlook / Microsoft 365.

Connection timed out or refused

Section titled “Connection timed out or refused”
  • Port 465 needs Use secure (TLS/SSL) on; ports 587 and 25 need it off.
  • Check the host name for typos.

Emails land in spam

Section titled “Emails land in spam”
  • Send from an address on your own domain and set up SPF, DKIM and DMARC. See the checklist.

Still stuck?

Section titled “Still stuck?”

Check the error in Email Delivery Logs, then contact support from the app with the error message.