With every subscription of Norton antivirus comes a product activation key. Without it, you cannot activate your Norton subscription and unlock the full security features of Norton antivirus. Here is how you can retrieve the Norton license activation code. If you have made the purchase from norton.com/setup page, the key will be in the mail sent by Norton after the checkout process. If you have a boxed version of Norton antivirus purchased from a retail store the key will be at the back of the retail card included with the package.