"To prevent browser warnings, use an SSL certificate with a common name or subject alternative name that contains the fully-qualified domain name of the server that hosts the certificate."
If the domain name (FQDN) in the TLS/SSL certificate doesn't match exactly the domain name displayed in the address bar of the browser, the browser stops the connection to the website and displays a name mismatch error. Errors create mistrust when connecting to a site and can cause clients to avoid your site (see Name Mismatch in Web Browser).
When you order a TLS/SSL certificate, the domain name on the TLS/SSL certificate must match the domain name for the website shown in the address bar of the browser exactly. For example, to get a certificate for www.example.com, you must add www.example.com as a common name or SANs (FQDN) in the order form.
DigiCert is the world’s premier provider of high—assurance digital certificates—providing trusted SSL, private and managed PKI deployments, and device certificates for the emerging IoT market. Since our founding almost fifteen years ago, we’ve been driven by the idea of finding a better way. A better way to provide authentication on the internet. A better way to tailor solutions to our customer’s needs. Now, we’ve added Symantec’s experience and talent to our legacy of innovation to find a better way to lead the industry forward, and build greater trust in identity and digital interactions.
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