More than 1.5 billion devices used Windows 7 and earlier versions of the system at the time of Windows 8's launch, making the OS both the most popular of its kind and one of the company's key sources of revenue.

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This problem was especially thorny for Microsoft because Virtual PC allows Windows 7 users to run applications designed for older Windows versions in a virtualized environment on their Windows 7 machines.

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BlackBerry, Windows Phone 7 and Nokia versions are on the way.

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Because neither IE6 or IE7 are supported by Windows 7, a lot of enterprises are still running their computers on Windows XP, old versions of Java, and IE6 or IE7.

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Adobe has just released a security update for Flash Player 11.2.202.233 and earlier versions for Windows, Macintosh and Linux, Adobe Flash Player 11.1.115.7 and earlier versions for Android 4.x, and Adobe Flash Player 11.1.111.8 and earlier versions for Android 3.x and 2.x.

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By contrast, Windows 7, Vista, OS X Tiger, Leopard, Snow Leopard and versions of the Linux kernel released after September 2009 are all 4K aware.

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The released versions run on the new Windows Phone 8 handsets, as well as the existing Windows Phone 7.x devices.

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