Microsoft has announced that it sold 20 million consumer copies of Windows Vista globally in February.

The operating system, which went on sale on January 30th, sold at almost double the pace of Windows XP, which sold 17 million units in its first two months on release in 2001.

"We are encouraged to see such a positive consumer response to Windows Vista right out of the gate," said corporate VP of the Windows business group at Microsoft Bill Veghte.

"While it’s very early in the product lifecycle, we are setting a foundation for Windows Vista to become the fastest-adopted version of Windows ever."

However, the Associated Press reports that Michael A. Silver, VP of research at technology analyst group Gartner, said Vista sales “probably should be more”.

Silver pointed out that 51 million PCs were sold to consumers worldwide in 2002, whilst this year, Garter predicts 96 million consumers will buy a computer.