Although our life without the Internet isn't worth a day's purchase, we all realize that the Web is a real “source of evil” for Windows PC. Trojans, spyware, phishing sites – all this can expose your essential information or stop your puter from working at all. That's why, decent security software is a good start to keep it safe and block all sophisticated and well-directed attacks. Happily, there are plenty of freeware anti-viruses on the market, so you won't have to waste money to decide which is the best one for your situation.
avast! Free Antivirus
Being one of the top among freeware anti-viruses, avast! Free Antivirus provides solid protection and performance results. With its streamlined user interface, the application comprises all the significant safety capabilities, like web and e-mail shields, boot-time scanning, and a behavioral blocker. It has a minimal impact on your system performance and supports a so-called Salient or Gaming mode: the program won't show you any messages when you view full-screen videos or play games.
This is actually my personal choice in terms of an urgent layer of protection from multitude viruses and rootkit infections. It detects up to 99% of all known threats and doesn't slow down your PC performance at all. Thanks to the fully-fledged behavioral blocker, AVG AntiVrus turns in a good score in malware-blocking test and does a great cleanup job. When required, it performs a complete scan of your system and prevents any intruders trying to install itself without you knowing.
Avira Free Antivirus
This is another freeware solution to look for threats and eliminate them from your Windows system. It features a powerful virus scanner with outstanding detection rates of malware and has a decent scanner speed that will free you from infinite waiting. Still, in spite of its comprehensiveness, Avira Free Antivirus doesn't support e-mail or web scanning capabilities, which means that the app won't warn you of infected e-mails. Besides, the program holds an irritating advertising window that pop ups every time when it updates.
Panda Cloud Antivirus
This lightweight, cloud-based tool will offer you a real-time protection which is generally very high. Panda Cloud Antivirus can work alongside with other security utilities without any issues and removes every intruder that comes across. As the program applies cloud technology to get a quicker release of updates, it is able to do its job only when your Internet connection is working. Some may consider it to be a real downside, while for me it's confusing why people need an antivirus when they're offline.
COMODO Internet Security
Another security application that will protect you from various threat sources. It comes as a bundled firewall and antivirus program, allowing you to install both of them or just choose the needed one. The Firewall controls your connection traffic in real time, maintains the list of known malware, and detects any security leak. Additionally, the program comprises Defence+ technology aimed to protect critical system files and block malware before it installs.