Jul 12, 2011 10:35 GMT  ·  By

20 months after the commercial availability of Windows 7, Microsoft has sold in excess of 400 million copies of the operating system. The new statistics were shared with participants at the company’s Worldwide Partner Conference 2011 by Tami Reller, Corporate Vice President and CFO, Windows & Windows Live and Steve Ballmer, Chief Executive Officer.

Ballmer also compared the success of Windows 7 to that of a rival operating system, which he did not name, but the Apple Mac OS X jab was anything but subtle.

“Windows, we're selling a lot of Windows, and we've got a lot of competition in the Windows business. But we're driving hard with just in the last year alone 350 million, 350 million new PCs sold. That might compare with numbers from other guys that are in the 20 million range. Now, 20 is too much, but 350, last time I checked, is a lot more than 20,” he stated.

The software giant continues to claims that Windows 7’s momentum is preserved even with the first details on Windows 8 made public this year.

I already predicted that Microsoft will sell over 600 or even 650 million Windows 7 licenses by the end of 2011, but it’s easy to see that sales of the platform will not be slowing down anytime soon. After all, Windows 7 is the only valid option for customers that want new Windows computers.

“So, last year I shared with you that, at a rate of seven copies per second, 150 million Windows licenses had been sold in the first seven months. That's the fastest, strongest start in the history of any OS. So, let me put the 400 million copies of Windows 7 that Steve mentioned earlier into context. That is three times the pace of Windows XP. Today, 27 percent of the Internet runs Windows 7,” Reller added.

XP continue to be king on the OS market, but this will change, most probably in 2012. Windows 7 is currently runner-up, but Microsoft still has to sell a few hundred million licenses for it to dislodge XP from its current position.

Of course, with WPC being a partner-focused event, the Redmond company could only credit its partners for the success of Windows 7.

“At the center of all of this success, all of this momentum is you, our partners, partners across the hardware ecosystem, our retail partners who delight consumers every day, ISVs and developers, solution partners, distributors, and resellers. Thank you,” Reller said.

“We are so grateful for the strong partnership that we have forged, first through the successful launch of Windows 7, and now as we continue on the path of helping our customers deploy Windows 7 across their enterprises.”

Windows 7 Service Pack 1 (SP1) RTM Build 7601.17514.101119-1850 and Windows Server 2008 R2 Service Pack 1 (SP1) RTM are available for download here.

Windows 7 RTM Enterprise 90-Day Evaluation is available for download here.