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In terms of what you need to add to your system many computer users will find that in a real world situation their choice of antivirus software is the most important. The reason for this is that many systems are already protected to some degree from outside intrusions by routers that have powerful firewall capabilities and also Windows XP, Vista or Windows 7 have limited firewall capabilities built in. For those systems that are not behind a firewall router or are without the firewall feature of Windows XP, Vista or Windows 7 then adding a software firewall is just as important as adding a good antivirus application.
There are a number of very good free antivirus programs available from a variety of sources. When considering free antivirus software be sure it is as good as a paid program or look elsewhere, because free doesn’t have to mean low quality or limited features as you will see from the following selections.
Avira AntiVir Personal Free Version
Users got to love AntiVir Personal Edition because of the 1 Year activation period for free regardless being registered or not. It can reliably protects your private computer against dangerous viruses, worms, Trojans and costly dialers. This program uses very few computer resources so is especially good for older computers. AntiVir can run in Windows Safe Mode so can be helpful if you are unable to get Windows to boot.
PC Tools AntiVirus Free Edition
This is a new free antivirus application from PC Tools. It can detect, quarantine, disinfect and destroy viruses, worms and Trojans. This free edition even includes real-time protection and comprehensive system screening to keep your system running safe and virus free.
Download Free PC Tools Antivirus
AVG Anti Virus Free Edition
Download the new and latest version of this top free antivirus product. This new version has an improved virus detection engine based on more accurate heuristics and NTFS data stream scanning. It also has a smaller installation ‘footprint’ and an improved user interface.
Avast! Antivirus Free Antivirus
This antivirus program is available free for home users. It is a complete antivirus solution and will do a great job protecting your computer from viruses. This newest version features better detection levels, together with higher performance. You can expect 100% detection of viruses already spreading between users and even excellent detection of Trojan horses.
This great free antivirus application can eliminates viruses, trojans and even worms from both desktops and networks. It offers constant protection with on-access scanning working in real-time. A powerful feature is the proactive heuristic analysis that can even intercept unknown threats. Updates of virus definitions are provided automatically on a daily basis. Any suspicious files it identifies are isolated in quarantine thereby preventing infection. This antivirus software is very easy to install and use.