SAN FRANCISCO, US - Microsoft said Thursday that cybercriminals are already hawking booby-trapped versions of just-released Windows 7 operating system software.

"It's so important for customers to get their copies of Windows from a trusted source," Joe Williams, general manager, Worldwide Genuine Windows at Microsoft, said in an interview posted at the company's official website.

"In the last few days we've seen reports of illegitimate distributions of the release candidate of our latest Windows operating system, Windows 7, being offered in a way that is designed to infect a customer's PC with malware."

A nearly-final version of Windows 7 made its world debut on Tuesday, giving people a chance to tell Microsoft what they love or hate about the new-generation operating system.

Microsoft is making Windows 7 Release Candidate (RC) available as it puts finishing touches on the operating system that will replace Vista.

The US software colossus has touted anti-piracy protections it built into Windows 7 to thwart the spread of illegal copies of the operating system.

Windows 7 anti-piracy guards build on technology built into Vista, according to Williams. For example, pop-up boxes will warn people when unauthorized copies of software are spied on computers.

"With Windows Vista, we made significant strides in reducing the threat pirated copies posed to customers, our partners and Microsoft software, and we anticipate we'll do even better with Windows 7," Williams said.

Microsoft decried software piracy as a pervasive problem that costs the world economy more than 45 billion dollars annually and exposes users to risks of identity theft, system crashes, and data loss.

Williams said Microsoft research shows that as many as a third of the company's customers worldwide may be running counterfeit copies of Windows.

"We see many cases of customers who wanted to buy genuine software and believed they did, only to find out later that they were victims of software piracy," Williams said.

Windows operating systems are used in about 90 percent of the world's computers, according to industry figures. --AFP