An outgoing email may fail because its connection is inactive or the provider rejected its credentials. Start with the message’s log entry.
- Open Email Logs and find the message. Its status and error message show what the provider reported.
- Open the connection it should have used, under Mailers, and confirm it is switched on.
- Click Verify credentials (or Re-verify credentials) on the connection to check them with the provider again.
- If it still fails, turn on Log mailer resolution to PHP error log in Settings → Logging & Retention, send the
email again, and check your server’s PHP error log for the line tagged
[boolean-smtp]. It names the connection and transport BooleanSMTP chose.
If a test reported success but did not arrive, follow the missing-email checks. For a failed message that is not retrying, see Fallback and retries.