You may encounter this error when you try to activate your Norton product which you have already installed on a different device from the email installation invite. You can manually enter your product key to activate your product when prompted. If any kind of issues you are facing in with Norton setup , all you need is to take help of http://Norton.com/nu16 technical support team or call on toll free number 1-888-827-9060.
Alternately, you can send a new email install invitation from your Norton account to install the product or reinstall the product from your Norton account.
norton.com/setup | Norton Setup Download & Install with Product Key