BEIJING, Oct 22 (Reuters) - Chinese Internet users have expressed fury at Microsoft's launch of an anti-piracy tool targeting Chinese computer users to ensure they buy genuine software.

The "Windows Genuine Advantage" programme, which turns the user's screen black if the installed software fails a validation test, is Microsoft's latest weapon in its war on piracy in China, where the vast majority of 200 million computer users are believed to be using counterfeit software, unwittingly or not.

"Why is Microsoft automatically connected with my computer? The computer is mine!" one angry blogger wrote on popular Chinese web portal Sina.com. "Microsoft has no right to control my hardware without my agreement."

Another blogger railed over the cost of authorised versions.

"If the price of genuine software was lower than the fake one, who would buy the fake one?" he wrote.

A visitor to a Beijing internet cafe said Microsoft was violating people's rights.

"If, when I'm programming, the computer screen goes black, that will probably cause some important information to be lost," he said. "Who will pay me for my loss then?"

Dong Zhengwei, 35, a Beijing lawyer, described Microsoft as the "biggest hacker in China with its intrusion into users' computer systems without their agreement or any judicial authority", the China Daily said.

"Microsoft's measure will cause serious functional damage to users' computers and, according to China's criminal law, the company can stand accused of breaching and hacking into computer systems," he was quoted as saying.

"I respect the right of Microsoft to protect its intellectual property, but it is taking on the wrong target with wrong measures. They should target producers and sellers of fake software, not users."

The software giant defended the programme on its website as part of its "commitment to help protect its intellectual property and to help you avoid problems before they happen".

"The purpose ... is to help our customers to determine (if) genuine software is installed on their computers," Microsoft told Reuters.

(Written by Kitty Bu; Reporting by Beijing Newsroom; Editing by Nick Macfie)

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