As the business of spyware proliferates and grows in complexity, companies are looking for ways to quickly rid their PCs of a problem that has evolved from a pesky plaque that slows system performance to an outright security threat for corporate data.

"We don't want some third-party provider installing some software without our knowledge," says Brady Brown, network administrator and project manager for Mustang Engineering LP. Late last year, the engineering design and project management company's IT department realized that 25% of the help-desk calls it received were for anomalies it couldn't explain. At Mustang, engineers were having trouble running their complex programs on their PCs, while administrative workers would at times have difficulty using e-mail. "User frustration was on the increase," Brown says. "We realized we had to do something or it would get worse."

Mustang addressed its spyware problem by implementing a Blue Coat Systems Inc. ProxySG network appliance to scan Web content for known spyware signatures and block potential spyware downloads. "We didn't have to pay a visit to the desktop or implement any client software," Brown says. "Our help-desk calls have all but ended regarding any spyware." This takes a strain off users, the IT staff, and the network itself.

Blue Coat's technology also detected spyware trying to connect with the Internet, says Gene Atteberry, manager of Mustang's information systems group. "We don't know if this was a malicious act or not because some spyware and adware is used just to summarize user behavior," he adds.

Such concerns have prompted the government to take action against companies responsible for distributing spyware. The Federal Trade Commission last week testified before the Senate Committee on Commerce, Science, and Transportation Subcommittee on Trade, Tourism, and Economic Development about the dangers of spyware. Spyware and other "malware" downloaded to consumers' computers without their consent can cause problems ranging from sluggish computer performance to loss of sensitive personal data, said FTC Chairman Deborah Platt Majoras.

The FTC has also launched several lawsuits against companies suspected of tricking computer users into downloading spyware. In one such case, the FTC v. Odysseus Marketing Inc., the government alleges Odysseus used deceptive claims that their free software would make illegal peer-to-peer file sharing anonymous. They did not disclose that their software would automatically install other, harmful software on consumers' computers, according to the FTC. The agency has also gone after Seismic Entertainment, stating that company engaged in "drive-by" downloads to install their software. The agency charged that downloading software without consumers' consent was unfair, in violation of the FTC Act, and a federal district court judge barred the defendants from distributing their software in that way, according to the FTC.

In August, Advertising.com Inc., now a subsidiary of America Online Inc., agreed to settle FTC charges that it violated federal law by offering free security software, but failing to disclose adequately that adware was bundled with that software.

What makes spyware particularly ominous is its ability to infect PCs even when users are operating within the parameters of their companies' security policies. "Usually, it's not something the user does," Brown says. Compounding the problem, some security software providers are reluctant to classify spyware or adware as security threats because they may serve some business purpose. Says Brown, "That makes it particularly difficult for us to block."