Utah's Spyware Control Act was sidelined in state court last June by a judge granting a temporary injunction for a New York-based pop-up ad company. WhenU.com claimed the Utah law was unconstitutional because Internet advertising is a matter of interstate commerce subject to federal, not state, jurisdiction.

Now a new law from Rep. Stephen Urquhart, R-St. George, solves the legal problems and still keeps advertisers from embedding spyware inside personal computers connected to the Internet, he said.

Urquhart's bill advanced out of a House committee on Monday and is expected to gain full legislative approval, taking effect July 1.

The new law requires advertising companies to pause before transmitting spyware and inquire whether the recipient is a Utah resident. If so, they would be prohibited from remotely installing spyware on that computer.

State lawyers contend Utah has jurisdiction in the state over spyware that generates annoying pop-up ads and can slow a computer's functioning to a crawl. Two Utah companies, Overstock.com and 1-800 Contacts, have complained that WhenU ads cost them millions by inundating their Web sites with competitors' ads.

California Gov. Arnold Schwarzenegger signed the only other anti-spyware law in the country, but Urquhart said several more states are looking to adopt similar bans. Utah took the lead as a state with the highest per-capita Internet usage outside of Alaska, but Urquhart conceded the law was hastily written and needed to be overhauled.

People often unknowingly add spyware to their computers when they download free software or visit certain Web sites. It can track their keystrokes, Web site visits and copy such personal information as passwords or credit card numbers. It also can generate pop-up ads specific to the Web page a person is viewing.

''This is software that is on your computer - and you don't want it there. You didn't ask for it,'' said Urquhart.

It takes concerted action and some skill to remove spyware programs from a personal computer - a fight that may never end because of a technological ''arms race'' between spyware companies and hackers trying to defeat them, he said.

Urquhart's bill doesn't give computer users the right to sue spyware companies for violations. They'd have to ask the attorney general's office to take legal action. The old bill left enforcement to companies who had to prove they were losing sales to a spyware operation.