Bought a new PC last November and loaded Norton Internet Security 2012 onto it same day without issues. Norton updates automatically to the 2013 version as they have dropped the yearly cycle to always provide the latest version during the period of your license.Looks like another issue may be causing your problems; have you taken off the antivirus installed on the pc before installing Norton? I would always put Norton above most other security suites out there, the light footprint and speed more than make up for the slightly better protection provided by bit-defender which results in a slower responding pc. incidentally, Webroot is more than worth a try-- no real footprint or slowdown of any type plus excellent protection-available for a free 6 month trial with facebook -it's all about horses for course. Hope you get it sorted!!
iMac Pro review