A few vendors either declined participation in our comparative review of enterprise antispyware products or didn't meet our qualifications for participation. Primary among these absences, Symantec Antivirus didn't meet the enterprise-level spyware-removal criteria that we established for participation, and McAfee declined participation, citing a pending release of a new version of McAfee Antispyware Enterprise, not yet ready for review.

Other vendors that offer enterprise solutions simply didn't respond to our request for review software. These products include XBlock Systems' X-Cleaner Enterprise Edition and GIANT Company Software's former offering, which Microsoft now owns. Two vendors—InterMute, which makes SpySubtract Enterprise Edition, and Webroot Software, which makes Spy Sweeper Enterprise—intended to participate, but ultimately didn't take part because of product revisions or other circumstances. I didn't include products such as Lavasoft's Ad-Aware and SpyBot-S&D because they don't currently offer centralized management features to facilitate enterprise usage and control. Products such as Prevx Enterprise and WebSense Enterprise provide host-intrusion prevention and are terrific tools for keeping malware out of your company network, but these types of tools didn't fit the criteria we established for spyware removal from client systems.