First time the authorities have publicly warned a company.
Microsoft has set a 20 day deadline to answer the questions about the compatibility and bundling issues related to its Windows OS and Office software suite, to the State Administration for Industry and Commerce of China.
The authorities are expected to meet with David Chen, the senior executive who takes care of the legal and corporate affairs of the company in China about the antitrust case.
Reportedly the verification code used by Microsoft has attracted a number of complaints from Chinese companies, which led to the investigation.
Verification codes are used to restrict and avoid software piracy but it also restricts users by only allowing them to get updates and support only form the manufacturer which said to be in violation of China's anti-monopoly law.
Recently, Microsoft have had a tough time in China, as authorities started investigating the company for violating the anti-trust policy, when it was reported that the software had a backdoor which could leak valuable information.
The issue led to ban of Windows software from official use and China is reportedly developing its own OS to be used for government purpose and to break the monopoly that foreign software makers.