To install a certificate on C2Net Stronghold follow the instructions below:

Save your server certificate as a text file.
Install the new certificate using getca, this utility is normally installed in /bin:

getca myhostname < /server certificate file location and name
Where: myhostname is the common name of the Web server for which the certificate was requested (this is the same as specified when you ran genkey) and '/server certificate file location and name' is the name of the server certificate file. This will save the certificate in the file /ssl/certs/myhostname.cert.

Restart your web server