The Secure Sockets Layer (SSL) protocol provides for secure communication between Serna and a remote HTTP or WebDAV server.
Serna initiates SSL connection on HTTP/WebDAV requests to a remote server using the HTTPS protocol ( https://).
The server certificate was issued by a trusted party.
The incoming server certificate must be signed by one of your CA certificates. Otherwise, the connection will be rejected and the Server Certified by an Unknown Authority message will appear.
Figure 1. Server Certified by an Unknown Authority message.

The server certificate is valid.
The incoming server certificate must be valid. Otherwise, the connection will be rejected and the Server Certificate Expired message or the Server Certificate Not Yet Valid message will appear.
Figure 2. Server Certificate Expired message.

To view the server certificate, click the View Certificate button.
The server certificate is related to the site contacted.
The hostname for which the incoming server certificate was issued must match the entered hostname of the server. Otherwise, the connection will be rejected and the Security Error: Domain Name Mismatch message will appear.
Figure 3. Security Error: Domain Name Mismatch message.

To view the server certificate, click the View Certificate button.
You can force the connection with untrusted servers. In this case, SSL warnings will be shown just once, and Serna will continue establishing the connection.