Microsoft is keeping mum on sales figures of Windows Vista, despite its chief operating officer claiming that 60 million units have been sold.
The software maker, however, declined to confirm the figure that Kevin Turner told financial analysts last week, throwing into confusion how successful its latest operating system has been.
But, approached by ZDNet Australia's sister site ZDNet.co.uk for confirmation, Microsoft could only confirm that it had sold 40 million, saying the last figure is two months old.
If Microsoft's figures are to be believed, this means Vista sales are flat. Turner's figures mean that 20 million copies of Vista have been sold, on a wholesale basis at least, over the last two months, with 40 million sold in the first four months since the consumer launch in January.
But, despite the uncertainty, Turner seized the opportunity for a spot of publicity. "By our math, we eclipse the entire installed base of Apple in the first five weeks that this product shipped," he said.
A Microsoft spokesperson added: "Windows Vista is on track to be the fastest-selling operating system in Microsoft's history. IDC says that, for every dollar of Microsoft revenue from Windows Vista in 2008, the ecosystem beyond Microsoft will reap approximately $22".
Colin Barker reported for ZDNet UK from London