China this week banned Microsofts new Windows 8 operating system from government computers, catching the American technology company by surprise. The ban was issued under a government notice about the use of energy-efficient technology, but Chinas state-run Xinhua news agency reported Tuesday that the move was motivated by security concerns that arose after Microsoft ended support for Windows XP. According to Xinhua, the majority of Chinese government computer still run Windows XP, and the operating system commands 70 percent of Chinas market. the Chinese government obviously cannot ignore the risks.