If you use McAfee’s anti-virus program and have Windows XP with SP 3, you may have noticed last week that your PC was shutting down every 60 seconds. That was because McAfee pushed out an update that it now admits wasn’t properly tested. To apologize, the company says it will reimburse you for repairs (although it hasn’t provided details on this yet), and it’s offering everyone who was affected a free 2-year extension of the service. Should you take the offer and call it even? Seth Rosenblatt at Cnet says you shouldn’t bother.