For users of Microsoft Windows operating systems, antivirus and security software is simply a fact of life. The following AV and security applications are my top recommendations for personal use or for small businesses. I have taken into account effectiveness (how well does the software prevent installation of malicious software), use of resources (how much does the software impact the overall performance of the computer), and user friendliness (how easy is it for an average user to download, install, and use). They are listed in alphabetical order.
Please be aware that while most of these companies allow their software to be downloaded and installed free of charge for personal, residential purposes, doing so on a computer belonging to a business of any kind most likely violates the terms and conditions of use, and constitutes illegal use of the software. This will be addressed in the reviews below, but please read all End User License Agreements (EULAs) carefully before installing.
One other note on computer security: No security software is 100% infallible. It is possible for a computer to become infected with malicious software even with the latest and greatest security software installed. Users still need to exercise caution and common sense when visiting websites, downloading files, or opening e-mail attachments. If you suspect that your computer might be compromised for any reason, you should immediately run a full system scan with whatever security software you have installed. If any threats are detected and removed, the computer needs to be shut down, restarted, and a second full system scan run to be sure the threats are not being reinstalled when the computer boots up. When in doubt, turn the computer off and call a professional to diagnose and remove any threats.
Clam AV is a Free Open Source Software (FOSS) antivirus application offered under the Gnu General Public License (GPL), meaning it is freely available to anyone to download and install. Clam AV is not my first recommendation for home users, but it is a viable option for small businesses who want good basic antivirus protection without the licensing headaches usually involved with corporate software. Clam AV also runs from portable USB devices, which makes scanning heavily infected computers much easier.
HijackThis is a free scanner that scans Windows Registry for malicious entries other scanners might miss. It is extremely useful in targeting malicious software that is reinstalling itself when the infected computer is rebooted. HijackThis will run from portable devices. WARNING: This application should be utilized by experienced and advanced computer users ONLY! HijackThis scans reveal ALL objects that impact a computer’s boot and startup routine, both malicious and benign. HijackThis users need to have the knowledge necessary to distinguish between what needs to be removed and what needs to stay.
If, despite your best efforts, your computer is compromised with malicious software, MalwareBytes is one of the best applications at removing it. As with most security software, free and paid versions are available. The free version should be sufficient for most home users and should be installed as a companion to any other antivirus software installed. I recommend running a complete MalwareBytes scan on computers monthly to detect and remove anything the antivirus software may have missed.
Microsoft’s Defender is free for all users and incorporates nicely into the Desktop environment. It should be installed as a companion to an antivirus application. Currently only available for Windows 7.
Also available for free and incorporated well into the Microsoft Desktop environment, Security Essentials adds additional security on top of Defender and other installed security applications. Currently only available for Windows XP, Vista, and Windows 7.
The problem with many good firewalls for Android devices is that they require root access to work properly, and most people do not root their phones or tablets. Which is why NoRoot Firewall (NRF) is making this list of recommended software, because as its name implies, no root access is required. I tested NRF extensively on my personal Android phone for a few weeks before making the decision to not only keep it on the phone, but to include it on my Recommended Software page. NRF works quietly in the background, monitoring your phone’s data traffic and alerting you anytime an app attempts to send an outgoing connection. Because of this, there is some initial setup time involved letting NRF know what apps you know for sure you want to allow to connect to the outside world. After that, there will be a couple of weeks of going through NRF’s alerts to see what apps are trying to connect and where they’re trying to connect to. Some research is necessary to figure out what traffic is legitimate and what traffic should be blocked, so I would not recommend this app for novice users.
SpyBot has been around for a long time and, similar to MalwareBytes, excels at removing malicious software from compromised systems. SpyBot has expanded its role lately and now offers other forms of computer security as well. SpyBot – Search & Destroy is also one of the few security scanners that will run from external storage devices such as USB drives, which is incredibly useful for heavily damaged machines that will not boot properly. I do not recommend SpyBot for novice users.