No antivirus software will protect against viruses that are "in the wild" since there are no definitions (updates) to counter them. A sign of a good A/V vendor is how quickly a definition file is released following the discovery of a virus in the wild. But the key is that a virus must
first appear in the wild before an A/V vendor can write a detector for it; someone has to be first to get infected. This has happened on occasion here at Thermwood and we use the
commercial edition of McAfee. Every time it has happened, the user tried to install something "free". (eCabinet Systems, excepted of course!

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In actuality, there really are very, very few viruses that are written today. Most of the infections are "trojans", which are infections promising to be one thing (ie: a video codec) and turn out to be another (spam generator). Trojans don't really fall under the definition of "virus" because viruses are self-replicating, where trojans usually require user interaction of some method like clicking "OK" to install the codec. Some trojans don't require a user to click OK because the computer isn't up-to-date with Adobe Acrobat, Adobe Reader, Adobe Shockwave, Apple Quicktime, Java, or Windows updates; keep your computer patched monthly. Microsoft releases patches on the second Tuesday of every month, which is quickly followed by what I call "Wicked Wednesday" when nasties are developed for the newly-announced vulnerabilities.
The best antivirus software out there is the organ between your ears. Stay away from questionable sites that offer "free" software for download. If a Facebook or MySpace friend mysteriously sends you a link to a web site that's out of the norm for that friend, ask him or her about it before clicking the link. To avoid getting spam, don't do the chain email stuff and ask your friends to not include you on their email forwarding lists. Most of that stuff is untrue anyway. Question emails you get that have attachments, especially ZIP and PDF ones. Be smart; live on the side of caution on the Internet.