The Internet is teeming with malware that can infect your computer, and it's important to use security software to protect yourself. To evaluate these products, Consumer Reports visited 75 dangerous websites in a secure testing environment. We also infected our test computers, which were running Windows 8.1, with more than 100 pieces of malware. Included in those malware files was the Cryptolocker virus, which encrypts photo, video, and document files, then demands the user buy decryption software to get their files back. Once all the test machines were infected, we got to work trying out four free and 14 fee-based security-software packages.

You’ll find detailed test results for the software in our Ratings. We also came to some conclusions that will help you decide which program will work best for you. Here’s a rundown.

  • Free software, such as Avira Free Antivirus 2015, is good enough for most users. It provides ample protection against websites that deliver malicious software, and was quick to identify new types of malware. If you decide to go with free software, make sure you download it from the official manufacturer website, and double-check that you’re not grabbing a fee-based product by mistake.
  • The freebies do lack a few essentials. First, they provide little or no protection against phishing, where cyberthieves try to trick you into giving up credentials such as your password and log-in. That’s easy to fix with a free toolbar like McAfee Site Advisor or Netcraft. These add a bit more protection than most browsers provide. Site Advisor, for example, puts site-legitimacy icons right into search results. Depending on how well your e-mail program sorts out junk mail, you may also want to add anti-spam to your free security package. We like SPAMfighter.

Check our security software buying guide and Ratings for more information.

  • For most users, Windows’ firewall offers enough protection, keeping malicious software from being downloaded onto your computer. The Windows firewall is turned on by default for Windows XP and later. But there are some users who can benefit from the two-way firewall included in a fee-based suite such as Symantec’s Norton Security. For example, if you use remote-access software, your computer is vulnerable to attempts to grab data from it.
  • If something’s wrong with your computer’s security, clear warnings are essential to helping you mop things up. We evaluate such warnings and include the results in our Ease of Use score—both ESET Smart Security 8 and Avira Free Antivirus 2015 scored well in this area.
  • Fee-based packages include features that are lacking in free software. If you’re looking for parental controls, or want to fight excessive spam, check out ESET and Symantec’s packages, as well as Bullguard Internet Security and G-Data Internet Security.
  • We tested Windows versions of these security-software packages. Apple computers are less vulnerable to malware, but Mac users should still protect themselves, to keep from spreading malware when exchanging files.

—Donna Tapellini

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