During the setup process an option is provided that enables Windows to attempt to activate itself automatically after three days of use.

在系统安装过程中有个选项可以允许用户填写激活信息，在使用Windows 3天之后自动激活。

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If you need to uninstall Windows 7 and go back to your previous version of Windows, you can activate it using the original product key.

如果需要卸载Windows 7，回到原来的Windows版本，可以用最初的序列号激活。

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By double clicking, just replace a letter or number, this will de-activate your Windows so you can change the key.

双击，修改一两个字母，就可以反激活你的windows。

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These were 25-digit activation keys used by big PC makers such as Dell and HP to activate Windows.

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This workaround relies on the fact that Microsoft is currently offering, for a time limited period, free upgrades for the Media Center add-on, and it is this process that is flawed because Microsoft does not check the validity of the original key used to activate the copy of Windows 8 Pro before dishing out another key.

FORBES: Microsoft Blunder Gives Pirates Free Copies Of Windows 8 Pro

Visually, the software looks like a version of Windows with touch-screen features, like a button to activate the keyboard, duct taped on top.

CNN: Mark Milian