A web server refers to the software that helps to deliver web content that can be accessed either through the Internet or through an intranet. The primary function of a web server is to store, process and deliver web pages to clients. The communication between client and server takes place using the Hypertext Transfer Protocol (HTTP). The most common use of web servers is to host websites, but there are other uses such as gaming, data storage, running enterprise applications, handling email, FTP, etc.
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How woud you know that this will work. You must knowthat wildcard certificate have only ONE PRIVATE KEY it just have more dns names in side of it. So if you wanted this working you must have for every wilde name A grade DNS to your server and import certificate inside every IIS instance.
You can also do one thing if you have more domains you can buy Certificate for your own microsoft Certification Autority and you can then make any certificate and all of them will be trusted becouse ROOT CA signs your CA and then you are save.
reed more here http://www.davidpashley.com/articles/cert-authority.html
Best practice is to make new Certificate on autority then use replace function on every servis for example in IIS it is import new certificate and then activate of it. After you replace certificate on every service you will go to managment panel of CA and revoke your certiciate (rewoking is dont trust this cert any more) and ict the same like destruction becouse it cant be used anywere.