Install information as shown in my account info

When I log in to my Norton account, it shows that I have  three installs, and that one install is available. I know of only two of my computers on which NIS is installed. How can I obtain indentifying information for the three computers included in Norton's records? 

Thanks!

When I log in to my Norton account, it shows that I have  three installs, and that one install is available. I know of only two of my computers on which NIS is installed. How can I obtain indentifying information for the three computers included in Norton's records?