Microsoft said it will begin selling a stripped-down, low-cost version of its Windows XP operating system in the emerging markets of Indonesia, Malaysia and Thailand in order to spread the use of computing and develop technology markets.

The move comes as the world's largest software maker grapples with the twin threats of piracy and the spread of Linux, the freely available operating system, in developing economies.

Windows XP Starter Edition will be available in the three countries in Southeast Asia from October as part of a one-year pilot programme and includes most of the features found in Windows, which runs on more than 90% of the world's PCs.

"It will be our most affordable Windows operating system offered to date," said Microsoft senior VP Maggie Wilderotter. "We are very excited to see what the reaction will be."

Windows XP Starter Edition will be shipped pre-installed on PCs. Microsoft has not yet set a price for the newest edition of Windows.

Although some features will not be available on Starter Edition, the operating system will be localised for each country's language and also include extra features and tools to make it easier for first-time computer users to use their PCs and connect to the Internet, Microsoft said.

Microsoft said it is also talking to governments of two other countries and will announce them later this year. The pilot programme will involve a total of five countries, Wilderotter said.

Many governments in Asia have also adopted Linux as a way to cut costs and address security concerns, since as "open source" software its basic programming code can be copied and modified freely by developers. Linux also runs on the same hardware as Windows.

Microsoft also faces the challenge of getting users in Asia, most notably China, to pay for its software, since much of it is distributed as pirated copies at a fraction of the price.

After the pilot ends, Microsoft said that it is considering the introduction of Windows XP Starter Edition for other developing markets, and hinted that it may even consider introducing the newest version of Windows on a wider scale.

"This does not preclude us from launching [Windows XP Starter Edition] in developed countries," Wilderotter said.