MDaemon supports the Secure Sockets Layer (SSL)/Transport Layer Security (TLS) protocol for SMTP, POP, and IMAP, and for Webmail's web server. The SSL protocol, developed by Netscape Communications Corporation, is the standard method for securing server/client Internet communications. It provides server authentication, data encryption, and optional client authentication for TCP/IP connection. Further, because SSL is built into all current major browsers, simply installing a valid digital certificate on your server will activate the connecting browser's SSL capabilities when connecting to Webmail.
If you are connecting to the standard mail ports via a mail client instead of using Webmail, MDaemon supports the STARTTLS extension over TLS for SMTP and IMAP, and the STLS extension for POP3. However, you must first have your client configured to use SSL, and it must support those extensions—not all mail clients support them.
Finally, you can also dedicate specific ports for SSL connections. This isn't required but can provide a further level of accessibility for clients that do not support certain SSL extensions. For example, some versions of Microsoft Outlook Express don't support STARTTLS for IMAP over the default mail port, but do support connections to dedicated SSL ports.
The options for enabling and configuring SSL are located under the SSL & TLS section of the Security Settings dialog at: Security » Security Settings » SSL & TLS. The SSL port settings for SMTP, POP3, and IMAP are located on the Ports screen at: Setup » Server Settings.
For information on creating and using SSL Certificates, see:
The TLS/SSL protocol is addressed in RFC-2246, which can be viewed at:
The STARTTLS extension for SMTP is addressed in RFC-3207, which can be viewed at:
Using TLS with the IMAP and POP3 protocols is addressed in RFC-2595, which can be viewed at: