Microsoft and Apple are having very different weeks.

The same day Microsoft’s stock plunged the most in 18 months on a middling earnings report and gloomy outlook, old rival Apple released a spectacularly good earnings report. The Cupertino, Calif., company earned more profit in the last three months of 2014 than any publicly traded company has ever reeled in during a quarter.

Microsoft sold $26.5 billion in software and devices, taking home $5.8 billion of that in profit. Apple, propelled by sales of its iPhone 6, logged sales of $74.6 billion, and a profit of $18 billion.

Nowhere is the contrast between the rivals clearer than their diverging fates in China.

Microsoft’s testy relationship with China just got a bit tougher.

The Chinese government has levied $137 million in back taxes and interest against the company, according to a report by China’s Xinhua state news service.

The report doesn’t identify Microsoft by name, labeling the target of the fine as “M,” described as a world-renowned U.S.-based company that started its Chinese subsidiary in 1995. Microsoft launched Microsoft (China) Co Ltd. in Beijing in 1995.

Xinhua’s report said that the company’s Chinese unit was losing money on paper, even as the Chinese subsidiaries of other firms in the industry were profitable. The investigation, Xinhua said, found the company was shipping its profits overseas in avoidance of domestic taxes.

Microsoft will be launching Xbox One in China on Sept. 29, the company said Tuesday.

Microsoft is delaying the launch of its Xbox One console in China — a launch that was supposed to take place this Tuesday but will now happen sometime before the end of the year.

Chinese antitrust officials  have given Microsoft 20 days to respond to questions about compatibility issues related to Windows and Office, as well as its use of verification codes, according to reports in The Wall Street Journal and Reuters.

Microsoft CEO Satya Nadella is scheduled to visit China next month, according to a report Thursday from Reuters.

Microsoft just made generally available Microsoft Azure in China, making it the first multinational company to offer public cloud services in China.

Microsoft has been steadily growing its cloud business into one of its largest revenue-generating divisions. Now it’s expanding its footprint in the fast-growing cloud market in Asia.

The company announced Wednesday that, in partnership with Chinese data center services provider 21Vianet, a public preview of Windows Azure in China will be available on June 6.

That makes Microsoft the first multinational organization to make public cloud services available in China. (Currently, the major cloud providers in China are the China-based Baidu, Alibaba and Tencent, according to 21Vianet.)