- Plesk Onyx for Linux
- Mail is not delivered to external mail servers;
/var/log/maillogthe following entry is found:
CONFIG_TEXT: postfix/smtp: 3E2F123A41AC: firstname.lastname@example.org, relay=smtp.sendgrid.net, delay=1140, delays=1139/0.11/0.48/0, dsn=4.0.0, status=deferred (SASL authentication failed; server smtp.sendgrid.net said: 535 Authentication failed: Bad username / password)
Incorrect SendGrid configuration.
Check steps from the SendGrid configuration article and make sure, that credentials for the SendGrid account are correct: Setting up SendGrid with Postfix as a relay server