Computer users around the world were left frustrated and furious yesterday as their PCs constantly restarted themselves every minute or so due to a Web worm that attacks flaws in the Windows operating system.

　　The worm, dubbed "LovSan" or "blaster," exploits holes in almost all versions of the Windows operating system and spreads to computers directly over the Internet without users having to open an e-mail message.

　　China was hit hard by the worm with some 12,000 people re-porting problems to the National Computer Emergency Response Center as of yesterday evening.

　　About 2,000 corporate and government networks in China were forced offline due to the worm, according to the center.

　　"We have yet to calculated the detailed figures, but the situation is serious because of the speed the worm spreads," said the center's director, Zhang Jian. "The danger level is high."

　　Industry analysts believe Shanghai was the hardest hit area in the country, probably due to the city's high Internet pene-tration rate.

　　"About 150 local people called our technology support hot line yesterday. It was the busiest day since the beginning of this year," said Jin Kai, the local technology director for Panda Software Corp, which makes anti-virus software.

　　Jin said corporate users accounted for about 80 percent of the calls to the hot line, with many of them hosting networks of 200 or more computers.

　　Many industry experts, how-ever, expect home users to be the biggest victims as they are least likely to have installed software patches made available earlier this week to prevent attacks.

　　While many victims will curse the hacker or hackers who created the worm, the computer geeks behind the software think someone else is to blame.

　　The worm's source code contains the hidden message: "Billy Gates why do you make this possible? Stop making money and fix your software."

　　That message isn't likely to get too many laughs from the owners of infected computers - of which there are 160,000 around the world by late last night, according to Symantec Corp, a giant in the anti-virus industry.

　　And the damage isn't finished. The worm will automatically attack Microsoft's Website by re-peatedly applying for a Windows update starting this Saturday.

　　That attack could take up so much bandwidth that it will seriously slow down Internet traffic, according to some experts.

　　"That will make the Internet crowded and greatly occupy the victim's computer resources," said Jin.

　　On monday, China's Ministry of Public Security warned computer users to download patches from Microsoft's Website to protect themselves against the worm.