- Plesk for Windows
Unable to send out email using port 465 in Plesk for Windows.
There is no SSL certificate applied to the mail server in Tools & Settings > SSL/TLS Certificates > Certificate for securing mail.
By default, Plesk configures MailEnable SMTP to use 465 port only for secure connections.
It is expected that MailEnable is not listening on port 465 unless SSL certificate for securing mail server is not installed.
Add a certificate in Tools & Settings > SSL/TLS Certificates > Certificate for securing mail.