On Tuesday, New York Attorney General Eliot Spitzer filed suit against another Web pop-up firm for allegedly installing malicious computer programs on PCs without users’ permission and distributing ads through the already installed “spyware,” the Associated Press reports via the New York Post.

Spyware is any computer program that installs itself on users’ PCs without their permission, and often, without their knowledge.

Spitzer accused Direct Revenue of installing millions of pop-up advertisement applications that also monitored the Web-surfing habits of infected machines’ users, according to the AP. The attorney general requested that a state court halt this practice, the AP reports.

“These applications are deceptive and unfair to consumers, bad for businesses that rely on efficient networks to do their jobs, and bad for online retailers that need consumers to trust and enjoy their online experience,” Spitzer said, according to the AP. “We will continue to side with consumers in their fight for control of their desktops.”

Spitzer already filed suit against another company for allegedly installing spyware and adware, and that company, Intermix Media, settled with the state in October after agreeing to pay $750,000 in fines, as well as penalties of $7.5 million over three years, according to the AP.

In the civil suit filed today in New York Supreme Court, Spitzer alleges that Direct Revenue or associated distributors offered up games and software to consumers free of charge, without mentioning that they contained adware downloads like VX2, Aurora and OfferOptimize, the AP reports.

Spitzer called such programs “drive-by downloads,” and said that once the adware programs were installed, Direct Revenue could monitor users’ Web-surfing history and deliver pop-up advertisements, according to the AP. Spitzer said the programs even attempted to override removal attempts and, in some instances, reinstall themselves, the AP reports.

The suit also names Josh Abram, Direct Revenue’s former chief executive, as a defendant, because Abram reportedly sent an e-mail to a distributor touting the efficiency of a new adware program that would “not be caught.”

For related news coverage, read N.Y. Files Suit Against Co. in E-Mail Sale Case.

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