Chinese officials gave Microsoft Corp. 20 days to explain what they called compatibility and bundling issues with its software, putting pressure on the software maker as it faces an antitrust probe into its business practices here. The State Administration for Industry and Commerce required the U.S. The agency said it issued the deadline in a meeting with Microsoft personnel Monday. David Chen, a Microsoft vice president who oversees legal and corporate affairs in China, was among the people in attendance, the agency said.