I have a few computers with updated anti-viruses (McAfee, Norton, E-trust, PC-Cillin). Any idea how viruses still get into these computers even though they have these updated anti-viruses on them? And any idea what the anti-virus companies are doing to combat this problem. I understand if it is a brand new virus and the definition has not come out, but some of these have been around for a while, (Klez, Mimic). Any ideas???