Well even the Pentagon gets hacked occasionally so I do not think there is anything that is 100% safe. They even have morphing viruses these days that can mutate at will. You have to do your best using all the tricks to avoid infections. Go to safe websites, don't put your key drive in places it should not go, be careful about keeping firewalls on and antivirus software updated, do scans frequently, and so forth. I am using AVG Free right now and so far so good. I have subscribed to both McAfee and Norton and I am doubtful they are worth the money although Norton was the better of the two.