Antivirus Software provides an essential layer of protection from a multitude of virus, trojan, worm, spyware, adware, dialer, keylogger and rootkit infections.

Here are several free antivirus programs that you can evaluate and decide which one best suit your need:

1) Avast! Free Antivirus –
http://www.avast.com/en-au/free-antivirus-download

2) Microsoft Security Essentials –
http://www.microsoft.com/Security_Essentials/

3) Panda Cloud Antivirus –
http://www.free-av.com/en/products/1/avira_antivir_personal__free_antivirus.html

4) AVG Anti-Virus Free Edition –
http://free.avg.com/au-en/homepage

5) Avira AntiVir Personal Edition –
http://www.free-av.com/en/products/1/avira_antivir_personal__free_antivirus.html