This error occurs when attempting to send email through JetEmail’s SMTP servers without having our required SPF record properly configured in your domain’s DNS settings.
[email protected] host relay.jetsmtp.net [103.173.0.0] SMTP error from remote mail server after end of data: 550 [SPF_INVALID] Blocked. See https://reports.jetsmtp.net/?id=000000000000000000&auth=smtpuser
SPF (Sender Policy Framework) is an email authentication method that helps prevent email spoofing. It specifies which mail servers are authorized to send email on behalf of your domain.