More than 20 million copies of Windows Vista were sold globally in February 2007, the first month of sales since its widespread consumer release.
That is significantly more than the 17 million copies of Windows XP that were sold in the first two months following its release in October 2001, Kevin Kutz, a director in Microsofts Windows client group, told eWEEK in an interview on March 26.
"These sales figures reflect global sales from retail, PC manufacturers and the Express Upgrade program, and indicate that we are on track to more than double the initial pace of sales for Windows XP, and for Vista to become the fastest adopted version of Windows ever," he said.
While Kutz declined to break down the numbers by region or even for each of the six Vista editions, he did say that sales were strong across the globe and that many of Vistas sales came through people buying new PCs.
"Sales of the premium editions were also strong," he added.
These sales figures were compiled by Microsoft based on sales reports from its retail and PC manufacturers over the period, as well as from the Express Upgrade program.
But Microsoft-Watch is reporting that the numbers just do not add up.
"By every reasonable measure — PCs and retail boxed sales — Microsofts numbers simply do not add up to the 20 million figure in one month," it says.
However, some Microsoft hardware partners, such as Dell, are seeing strong interest in the premium versions of Vista.
"Since the launch of Windows Vista, Dell consumer customers have overwhelmingly chosen premium versions of the operating system that enable them to have a richer experience with music, video, photography and other computing applications they choose," Neil Hand, the vice president of Dells Consumer Product Group, said in a statement.
Microsoft is expected to disclose more regional and version sales details when it releases its quarterly financial figures in late April.
Some analysts have said that the new anti-piracy and validation tools that Microsoft is shipping with Vista and Longhorn Server will help ensure there will be little corporate uptake of these operating systems in 2007.
Kutz did acknowledge that, historically, there tended to be a rush of sales immediately after a products launch, which varied according to the time of year.
"Its worth noting that with XP, which we launched in late October in advance of the holiday season, those figures captured some of the holiday rush, so you really have to go back to Windows 95, launched in August, to make a like-for-like comparison in terms of scale," he said.
"But generally, you do see a concentration of sales right after release and then things return to normal and you tend to track more with overall forecasting for PC sales, generally speaking," Kutz said.
Research firm Gartner said recently that it expects worldwide PC shipments to grow 10.5 percent to a total of 255.7 million units this year, with revenue slated to grow 4.6 percent to $213.7 billion.
While Microsoft had no details to share on what adoption had been like in the first month following the business launch of Vista to volume license customers on Nov. 30, Kutz said there has been "really good enthusiasm from major customers and we feel pretty good about current sales as far as business adoption is concerned."
Microsoft decided to make these figures available in response to robust interest in what consumer demand has been like for Vista and to give a fresh comparison to XP, he said.
Asked if early strong sales momentum has continued into March, Kutz would only say that Microsoft still remained pleased with the way sales were going.
With regard to sales of Office 2007 over the same period, Kutz said Microsoft was not disclosing any sales figures, adding that "the folk at Office are pleased right now with the initial response."
Editors Note: This story was updated to include information from Microsoft-Watch.