AVG
by:  Grisoft
website: www.grisoft.com/
support:
http://free.grisoft.com/doc/downloads-products/us/frt/0

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AVG is one of the first companies to provide support for a free version of their anti-virus software.  It is really reliable but, I found updates can be a little less seamless than they are portrayed to be.  It is a breeze to set-up and they have nice tech support and forums..and of course ITS FREE!!!

Going GEEK:

AVG didn't seem to update quite as often as Avast! but changed and update daily now.  I have used them for 5 years now have and I never encountered a virus, trojan, worm, etc...

Miscellaneous information:

Installation Reference Guide

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