BEIJING, CHINA: A top Chinese copyright official chided Microsoft for launching an "anti-piracy" tool that causes screens of computers using counterfeit software to turn black and said the company's prices were too high.

The U.S. software giant launched its "Windows Genuine Advantage" programme last week, prompting lawsuit threats and howls of indignation in China, where the vast majority of computer users are believed to be using counterfeit software, unwittingly or not.

National Copyright Administration Vice-Director Yan Xiaohong said his agency supported "the rights-safeguarding move taken by institutions including Microsoft", Xinhua news agency quoted him as saying in a report late on Monday.

But companies should "pay attention to the methods", Yan said.

"Whether the 'black-out' method should be adopted is open to question. Measures for safeguarding rights also need to be appropriate," Yan said.

Microsoft has defended the blackout programme as a measure to protect its intellectual property and help customers determine that they have legal software.

Dong Zhengwei, a Beijing lawyer, said Microsoft was abusing its market power by forcing users to verify the genuineness of their software and had filed a complaint to China's trade watchdog, the State Administration for Industry and Commerce, the China Daily said in separate report.

"Microsoft should be fined $1 billion," the paper quoted the lawyer as saying.

Yan said Microsoft's price policies needed to "fit the Chinese situation."

"The company adopted unified prices in the past without considering the income gap between developed and developing countries, so we need to kindly remind them that Chinese customers' affordability should be considered," Yan said.