To process an order to issue an SSL certificate, the Certification Authority must verify that the site really belongs to you. To do this, you just need to be able to validate your domain by performing the actions that can only be done by the owner of the domain or a person authorized by him. Three ways to validate a domain: The fastest and easiest way is to follow a link that the certification authority sends to one of the administrative addresses in your domain. Administrative addresses are addresses that begin with: postmaster@, hostmaster@, administrator@, admin@ or webmaster@ in your domain. Create a CNAME record for your domain that contains a unique code. Place a verification text file with the code on your site. The file is posted through a link that is not visible to site visitors. This method is not suitable for Wildcard and SAN certificates.