LIVONIA, Mich. (AP) — When Steven Paul Brown and his wife separated, authorities say he installed spy software on her computer that would allow him to track her every keystroke and read every file and message.

Buying the software is perfectly legal, but if a court determines Brown used it the way Michigan Attorney General Jennifer Granholm thinks he did, it could land him in prison for up to five years, Granholm said Wednesday.

"Just like breaking into someone's home, breaking into a person's computer is a crime," Granholm said. "These are crimes that hurt people because they make them feel vulnerable."

Brown, 41, was charged with installing an eavesdropping device, eavesdropping, using a computer to commit a crime and having unauthorized computer access. He could not be reached for comment Wednesday.

Granholm said Brown used a commercially available program called eBlaster to hack into his estranged wife's computer at her home in Warren this spring. The program caused all her Web surfing and Internet communication to be e-mailed to Brown as frequently as every 30 minutes without her knowledge, Granholm said.

When Brown allegedly shared some of that information with his estranged wife's friend, the Michigan Attorney General's High Tech Crime Unit was alerted and investigators seized Brown's computer equipment.

"People have to be very concerned about security," Granholm said. "You hate to be paranoid, but the reality is people get hacked all the time."

The eBlaster software, made by Spectorsoft, is advertised as a way to monitor computers while away. The Vero Beach, Fla., company's Web site reads: "Are you concerned about what your spouse, employees or children do on the Internet while you're away? You can't always be around to watch over their shoulders, so hire a second pair of eyes with eBlaster."