Requesting a Certificate Authority signed certificate
A certificate authority signed certificate is more likely than a self-signed certificate to be effective for SMTP/TLS communication, and can also be used for HTTPS communication. Before you proceed, determine the CA from which you want to purchase your certificate. Some possible CAs to use are listed on the Certificate Authority tab in the Control Center. However, other CAs are also supported.
For the common name, use the domain name or the fully qualified domain name of the computer where the certificate will be installed. Some CAs may not support certificates that are created using an IP address instead of a domain name for the common name. Check with your CAs.
Each CA has its own set of procedures to request certificates and issue certificates. Consult your CA for details and follow the instructions that are appropriate for your installation.
If you have a certificate authority signed certificate, you can add that certificate even if you have not submitted a certificate signing request. However, if you did not either generate a new certificate signing request in the Control Center, or export the certificate from a Symantec Messaging Gateway appliance, you must first modify the certificate.