How to Find My Fully Qualified Domain Name
A "qualified domain" is a collection of computers all connected to each other with the ability to transfer files from machine to machine. If you have an operating system that is capable of connecting to one of these domains (only the Professional and Ultimate editions of Windows can do so), your computer knows which domain to connect to because of a specified domain name. You can find your domain name under Windows' "System Properties" utility.
Click "Control Panel."
Open the "System" icon to open the "System Properties" utility.
Click the "Computer Name" tab. Your domain name will be listed in this window.