Before you can enroll for an SSL Server Certificate, you must generate a Certificate Signing Request (CSR) from your web server software. During the creation of the CSR, the following fields must be entered: Organization (O), Organizational Unit (OU), Country (C), State (S), Locality (L), and Common Name (CN). The Common Name field is often misunderstood and filled out incorrectly.
The Common Name is typically composed of Host + Domain Name and will look like
yoursite.com. SSL Server Certificates are specific to the Common Name that they have been issued to at the Host level.
The Common Name must be the same as the Web address you will be accessing when connecting to a secure site. For example, an SSL Server Certificate for the domain
domain.com will receive a browser warning if accessing a site named
secure.domain.com are different from
domain.com. You would need to create a CSR for the correct Common Name.
By default all Basic, Wildcard and Enterprise EV certificates ordered from SSL.com will automatically add
www. to any domain name registered. You can thus secure
www.domain.com when filling out the Common Name field automatically – just enter your own
domain.com and your certificate will automatically cover
When a Certificate will be used on an Intranet (or internal network), the Common Name may be one word, and it can also be the name of the server.