China's homegrown version of the Linux Ubuntu OS has racked up more than one million downloads in half a year.
The milestone for downloads of Ubuntu Kylin, part developed by the Chinese Ministry of Industry and Information Technology, comes as Microsoft prepares to end support for the country's most popular OS, Windows XP.
Windows XP is run by just under half of Chinese computer users according to figures from StatCounter, which tracks the OS used by visitors to websites worldwide.
The proportion of XP users has fallen in recent years, down from just over 60 percent in November 2012. While just over 40 percent of machines in China now run Windows 7, adoption of Windows 8 remains just below three percent, according to the same figures.
Last year, China's National Copyright Administration asked Microsoft to extend support for Windows XP in China, and resume sales of "low-cost" versions of Windows 7 that were discontinued at the launch of Windows 8.
Yan Xiaohong, deputy director of the National Copyright Administration, warned that failing to do so could hamper the uptake of genuine software in the country. The proportion of China's personal computers with pirated software installed fell to 77 percent in 2011, a record low, according to the Business Software Alliance.
There were 400,000 downloads of Ubuntu Kylin after its first release in April 2013, rising to more than 1.3m new downloads after its second release in October.
Relative to the Chinese population the number of downloads for Ubuntu Kylin is tiny, less than 0.1 percent of the 1.35 billion-strong population.
However Canonical, the company behind Ubuntu, claims the figure is impressive for a downloadable operating system, since in China, as elsewhere in the world, PC owners prefer to get their OS pre-installed when they buy a device.
Kylin has been designed to suit the needs of Chinese users, with a full Chinese user interface, bespoke Chinese applications and integration with domestic services: such as music search from Baidu in the dash. It also includes Kingsoft WPS, one of China's most popular office suites.
Canonical worked with the China Software and Integrated Promotions Centre (CSIP), part of the Chinese Ministry of Industry and Information Technology, and the Chinese National University of Defense Technology, on developing Kylin.
"Ubuntu Kylin is a professional open source community implementation based on Ubuntu for Chinese users, which offers users a secure, localized experience that will be updated frequently by the Joint Lab and community," said Dr Qiu ShanQinm, president of CSIP.
Another domestic Linux OS in China, Red Flag Linux, recently shutdown, according to a report by the site TechInAsia.