Of the six stand-alone products we reviewed for our October 2007 issue's antispyware feature, "Die, Spyware, Die!" PC Tools' Spyware Doctor 5.0 was the clear winner, outperforming the competition at detecting and removing our test set of adware and spyware samples. That performance, combined with solid features and support, earned the program our Best Buy distinction.

In tests performed by AV-Test.org, Spyware Doctor did a better job of identifying and uprooting adware than spyware. It detected 81 percent of our inactive adware samples and all ten actively running adware samples, and it successfully removed the files and Registry entries of almost all of the active adware samples. With spyware, however, Spyware Doctor spotted only 27 percent of our inactive banking-related spyware specimens and 43 percent of password-stealing spyware. Though it detected all of our active spyware samples except the password-stealing Trojan PSW.Maran, it successfully cleaned up only 70 percent of spyware files and Registry entries. Still, that performance put it ahead of the rest.

Spyware Doctor held up well in behavior-based detection tests, too, detecting additions to HKCU and HKLM 'Run' Registry keys (many malware threats target these) and preventing adware and spyware programs from changing Internet Explorer Search and Start pages. On the other hand, it didn't detect AV-Test.org's changes to the Hosts file, which spyware can manipulate to redirect you to a malicious Web site.

This well-designed program was a breeze to install. Three big buttons let you scan your PC for threats, clean up any problems the software finds, and activate real-time threat detection (it's on by default). The settings could use a little tweaking, however. By default, Spyware Doctor does not schedule system scans or turn on antirootkit protection; the latter decision serves to speed up scanning and to minimize false positives. (Incidentally, Spyware Doctor found eight of the nine inactive rootkits in our detection tests.) We also didn't like Spyware Doctor's penchant for flagging innocuous ad-tracking cookies as "infections;" on our brand-new Windows Vista test machine, the overzealous Doctor diagnosed 387 "infections" that turned out to be cookies from Google, The New York Times, and other reputable Web sites.

This program was the only one of the six we examined that provided basic, blacklist-based antiphishing protection (for Internet Explorer and for Firefox). Another positive was PC Tools' around-the-clock toll-free telephone support for U.S. customers alongside e-mail and Web-based support. For an extra $10, Spyware Doctor offers antivirus protection, which we did not test for this review.

If you're looking for comprehensive, easy-to-use adware and spyware protection, and you don't mind paying $30 for it, we recommend Spyware Doctor.

Ryan Naraine