Free Anti-Spyware

Free programs can help

Several highly regarded free anti-spyware programs are available, and reviews suggest using one or more of these to supplement paid versions of Spy Sweeper or Spyware Doctor. All the free programs have limited functionality, however, so they aren't the best choice as your primary anti-spyware defense.

In the past, many experts wrote that some free anti-spyware solutions were as robust as any of the commercial products. Now, they say that's no longer true. In tests, both Ad-Aware and Spybot Search & Destroy are not competitive with Spy Sweeper and Spyware Doctor.

If your computer is running Windows Vista, you already have Windows Defender, a free anti-spyware tool. Make sure real-time protection is turned on (the default option). The current version is 1.1. The program is also available as a free download for Windows XP users who accept Microsoft's Windows validation process. In PC World's tests, Windows Defender 1.1 is excellent at detecting adware, but barely removes half of it. It's much poorer at catching spyware. Ryan Naraine concludes, "Windows Defender is certainly better than nothing." He adds, "It combats adware and offers behavior-based protection that should block many threats, but if malicious spyware slips past Defender's first line of defense, you'll need something else to clean up the mess."

CNet.com's Robert Vamosi recommends that Windows Defender "be a part of your desktop antispyware collection," but for real protection he suggests a name-brand antivirus-plus-software application. On the plus side, Windows Defender is feature-rich and light on system resources, but in Vamosi's testing it came up short in both detection and removal.

Lavasoft Ad-Aware Free Anniversary Edition is a recent upgrade of a unique protection tool. Lavasoft Ad-Aware also comes in two commercial versions for home users -- Ad-Aware Plus (*Est. $30) and Ad-Aware Pro (*Est. $40), which reviewers say aren't competitive with the top freestanding anti-spyware programs. The major difference between the free and commercial versions is that the free version lacks anti-virus protection, advanced tools and real-time network protection. With 300 million downloads on CNet's Download.com, Ad-Aware is the site's most popular program. Users score it relatively high, although they're not as impressed as editors, who give it a near-perfect rating. Download.com says that Ad-Aware is easy on system resources and easy to use, but lacking in advanced features.

Safer Networking Spybot Search & Destroy 1.6 (free) was one of the first tools to combat spyware, and it is the most similar alternative to the commercial programs. Unlike Ad-Aware, Spybot does have some real-time protection. It blocks attempts to hijack your web browser and change items in your host file, and it has an immunization tool that modifies Internet Explorer to block malware from known perpetrators. It also supports real-time protection for alternative browsers such as Firefox and Opera. Spybot has 100 million downloads on Download.com, but editors downgrade their rating because of bugs and false positives. Overall, they call it "a good choice for those in search of a second antispyware program."

We also saw some positive reviews for Malwarebytes Anti-Malware 1.34. Download.com editors give it a high rating (4.5 out of five stars), and users largely concur, giving it the same rating after more than 1,000 votes. The biggest negative is that the free version is somewhat crippled in that it does not provide real-time protection or allow you to schedule updates or scans; for that you have to step up to the paid version (*est. $25). Otherwise, the program is easy to use, quick and effective.