An updated software that checks whether the user’s copy of Windows XP Pro is a genuine product. Alex Kochis who is the Microsoft director of product marketing and management said in a blog post that the change only affects XP Pro since it is “the product edition that is most often stolen.”
The article at PC World notes the two features in this update. First, the desktop screen background will be black the next time the user logs on his or her system if his or her copy is found to be pirated. The other feature is that it will display a banner which says that his or her operating system is not genuine.
Source: PC World

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