Even then, however, there are ways to circumvent the shut-down. Windows 8 Pro, the more expensive of the two public editions, includes "downgrade" rights that allow PC owners to legally install an older OS. OEMs and system builders can also use downgrade rights to sell a Windows 8- or Windows 8.1-licensed system, but factory-downgrade it to Windows 7 Professional before it ships.
Enterprises with volume license agreements are not at risk of losing access to Windows 7, as they are granted downgrade rights as part of those agreements. In other words, while Microsoft may try to stymie Windows 7 sales, the 2009 operating system will long remain a standard.
As of the end of November, approximately 46.6 percent of all personal computers ran Windows 7, according to Web measurement vendor Net Applications, a number that represented 51.3 percent of all the systems running Windows.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, or subscribe to Gregg's RSS feed . His email address is firstname.lastname@example.org.
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