If you have previously had Norton Installed the following info will assist you in finding your PIN.
Your PIN number is stored in Norton Security_PIN.txt in the following location:
In Windows 10/8/7/Vista: C:\Users\Users Name\My Documents\Symantec\Norton Security_PIN.txt
In Windows XP: C:\Documents and Settings\\My Documents\Symantec\Norton Security_PIN.txt
If this is an initial install on a new sytstem, or if you have moved and your Xfinity Service is in new loctkion, lt us know the circumstances. The following link should auto load the PIN when it activates.