The Chinese government has warned Microsoft against interfering in an anti-trust investigation into the firm by Chinese regulators, in a sign of increasingly frosty relations between the two countries.
The State Administration for Industry and Commerce (SAIC) in China formally launched an investigation last week against Microsoft, claiming there has been breach of anti-trust rules. The body also raided four of the firm's offices in China.
Microsoft has been accused by SAIC of violating China's anti-monopoly law from June 2013 as it didn't disclose relevant information about some security features and how it ties its software products together.
"Microsoft promised to respect Chinese law and fully cooperate with the SAIC's investigation work," the SAIC said.
Microsoft declined to comment on the latest salvo fired by the regulators but said earlier that its "business practices are designed to be compliant with Chinese law."
The software giant has taken quite a beating in the country in recent times. In April, Chinese state media accused Microsoft of "abusing its dominant market position" by terminating support for its XP operating system, used by 200 million people in China.
Later in May, the Chinese government stopped installation of Microsoft's Windows 8 operating system on computers used by the central government, amid suspicions of hacking.
American technology firms have been under the Chinese scanner since the cyber espionage efforts by National Security Agency were made public by Edward Snowden last year, though Microsoft has been quite vocal on its demand of NSA reform on the anniversary of Snowden leaks.
Chinese regulators are also pursuing Qualcomm, a maker of mobile device chips, for possible antitrust violations and overcharging Chinese customers.
The Chinese government has also started to examine the dependence of Chinese banks on computer servers made by IBM.