Updated for 2010-2011: Download great free software to keep your computer safe!
How well would you cope if all of the data on your computer was suddenly inaccessible? Or what if your credit card numbers were stolen online?
Unfortunately these are ever-present dangers. But there is free software available that will allow you to safely protect your computer.
In the past, running anti-virus software was enough to keep you protected. But nowadays, there are at least three components you’ll need for proper PC security:
None of these programs will guarantee that your computer is safe, but here are 10 free software applications you can use to help protect your personal data from harm. (Note also that many of these programs are intended for personal/home use only.)
Operating System Updates
If you are using Windows (like about 90% of web users) you need to make sure your copy of Windows is kept up-to-date using Windows Update. This protects you against any vulnerabilities or bugs that have been discovered in the operating system. The best solution is to make sure automatic updates are on, but if you choose to update manually, Microsoft recommends that you check for new updates once a week.
Probably the largest threat to your computer is spyware. Spyware can add annoyances to your web browsing like extra popups or redirecting you to inappropriate websites. Most dangerously, it can allow unscrupulous individuals to steal your personal information including credit card numbers or banking data.
Windows Defender from Microsoft won’t interfere with other spyware apps, so it’s a good idea to have it running even though it is not the most effective anti-spyware tool available. If you have Vista, make sure it’s turned on by going to Start > All Programs > Windows Defender, then Tools > Options, and under Administrator options, select or clear the Use Windows Defender checkbox. If you have XP, you can download Windows Defender for free from Microsoft’s website.
Malwarebytes’ Anti-Malware is described by CNet as a “surprisingly effective freeware antimalware tool.” Its free version is fast and generally very effective at identifying and removing spywar, trojans, and other troublesome software. (Note that realtime protection is only available in the paid version.)
Spybot Search & Destroy
Spybot S&D is lightweight and frequently updated. It scans your computer quickly compared to many other anti-spyware applications, and includes optional real-time (constant) protection. However its interface can be confusing so you’ll have to take a little time to learn how to use it.
Comprehensive guide on network security from Answers.com’s Networking Expert Chad Williamson.
Viruses used to be the most common computer threat. Today viruses are less common than spyware, but it is still necessary to run anti-virus software to keep your computer protected. Most anti-virus software continually scans your computer as you work so that you will immediately be alerted to potential threats.
Avast! is oddly named but it doesn’t take up a lot of system resources and includes “anti-rootkit” protection. (Rootkits are programs hackers use to access systems.) Free registration on the Avast! website is required to obtain a license key to use this software.
A third option for virus protection is Avira AntiVir, which requires no registration to download and use. It does not scan incoming or outgoing email, but it is usually fast when doing full-computer scans and runs constantly to keep you protected.
AVG Anti-Virus Free Edition
AVG was one of the first free anti-virus applications and is a reliable standard. Its newest version includes some new features and a new interface but has been criticized for slowing down your computer a bit more than previous releases, so it’s best for reasonably fast/recent computers.
A firewall moderates the data that is allowed in and out of your computer. Hardware firewalls (such as a router) prevents data (except the types that you choose) from entering or leaving your computer. Software firewalls can also monitor which programs are sending and receiving data and allow you to prevent individual applications from doing so.
Windows Firewall is included with Windows XP SP2 and Vista. Since you likely already have it, you might as well use it, even though it is less effective than other free solutions. To make sure it’s running, in XP go to Start > Control Panel > Windows Firewall … in Vista, go to Start > Control Panel > Security > Windows Firewall.
Comodo Firewall Pro
Comodo Firewall Pro is the highest rated free firewall program as judged by an independent security organization. It also includes some basic virus protection and spyware protection, but it should not be used as a replacement for those programs. Comodo is a good choice if you’re looking for a full featured free firewall solution.
The final software recommendation to keep you safe is using Mozilla Firefox or Google Chrome as your web browser instead of Internet Explorer. Although IE9 presents many significant improvements over previous versions, Firefox and Chrome (or Opera, another free competitor) are web browsers which include built-in security features to try to keep you safe from “phishing” sites (fake sites that try to trick you into entering personal information) and are not vulnerable to certain types of attacks that Internet Explorer is.
Of course the very best way to avoid spyware, viruses, and hacker attacks in the first place is to be cautious! Carefully choose which websites you visit, don’t click links in email or instant messages, and don’t install any software without researching it first. If you keep these guidelines in mind, you’ll be on the right track to keeping your personal computer and your data safe!
Disclaimer: All programs listed above should be considered “caveat emptor”: Use them at your own risk. No software or program will be entirely free from error or work properly in every situation. We disclaim all warranties, expressed or implied, including, and without limitation to, the warranties of merchantability and of fitness for any purpose stated by any program or website mentioned or linked to. Furthermore, we will assume no liability for damages of ANY kind (direct or consequential) which may result from the use of any program or resource listed.
 Matousec Transperent Security, “Firewall Challenge: Results & Comments” n.p. Cited 22 July 2008. Online: http://www.matousec.com/projects/firewall-challenge/results.php