Microsoft has sold some 60 million Windows 8 licences since the OS's launch, according to the finance and marketing head of Windows business, Tami Reller.
Reller was speaking at the Consumer Electronics Show (CES) in Las Vegas, where she told delegates that Windows 8 sales were growing in line with those of Windows 7, Reuters reports.
This is the second time Microsoft executives have revealed figures that appear to confound speculation that Windows 8 would fail to live up to expectations.
Reller, who was named as one of two executives to take over responsibility of the Windows business, had revealed at the end of November that the firm had sold 40 million licences for its new operating system.
This means that 20 million more licences have been sold since the end of November - getting closer to the sales that Windows 7 achieved, which averaged 19.4 million licences a month in its first nine months on the market.
Reller did not specify whether the figure included enterprise agreement and volume licence sales, or how many of the sales were bulk orders from PC manufacturers.
Windows 8 has been designed as much for touch-screen tablet and ultrabook devices as for traditional desktop PCs.
According to analyst firm Forrester, global corporate spending on ‘Wintel' PCs and tablets was down by four per cent in 2012 and will be flat in 2013 as firms slowly replace their old Windows PCs with Windows 8 devices.
Forrester believes that as demand and product quality improve, global sales of Wintel devices should see an increas of eight per cent in 2014.
But many are unconvinced, including the founder of video game development firm Valve who told The Verge that Windows 8 was a "giant sadness".
"Rather than everybody being all excited to buy a new PC, buying new software to run on it, we've had a 20 per cent plus decline in PC sales," he said.
"There's supposed to be a 40 per cent uptake, not a 20 per cent decline, so that's what really scares me. When I started using it I was like "oh my god..." I find [Windows 8] unusable," he added.