Microsoft Chairman Bill Gates says sales of Windows Vista have been "rapid", with more than 140 million copies sold worldwide.
Gates, speaking in Tokyo, said the figure represented "a very rapid sales rate," according to a Wall Street Journal report on Thursday.
Despite the sales figures, Microsoft has admitted to struggling with the public's perception of Vista. Windows XP, Vista's 7-year-old predecessor, is still popular among both businesses and consumers.
Microsoft already extended the deadline for ending XP sales to large computer makers one time, allowing sales through June 30, as opposed to ending them this past January. The software maker also granted a more narrow extension, allowing XP to be used on ultra-low-cost computers through 2010.
More recently, Microsoft CEO Steve Ballmer said that the company might reconsider its decision to stop selling XP next month.
While Microsoft ponders yet another stay of execution for Windows XP, it's readying a new version of Windows, being developed under the code name "Windows 7."