Two existing Antivirus Protection tools for windows

AVG Antivirus

Arguably the best free tool in the market, AVG Antivirus Free is a combined tool that serves as an antispyware, e-mail and URL scanner. It allows you to turn on auto scanning and update options in addition to updating virus definitions periodically. This tool is compatible with Windows 7/Vista/XP/2000. On the other hand, if you are looking for advanced features, you can also get them on this freeware. Features like set-and-forget are also integrated with this version of AVG.

Avira AntiVir Personal

The AntiVir Personal from Avira is a free antivirus that defends your PC from a wide range of malicious programs like Trojans, worms, spyware and adware along with other potential malware. Thus, this is a complete solution to viruses and malware related problems. The interface of this program is very user friendly which adds value along with its competent protective features. The only drawback of this security software is its complicated setup process which can give a tough time to the beginners. Besides being compatible with Windows 7, Windows Vista, Windows XP and Windows 2000, the Avira AntiVir Personal also has a version that is compatible with UNIX.