Microsoft has confirmed that its free security software will be available only to users running legitimate copies of Windows.
Security Essentials is a free anti-virus product that Microsoft is hoping will be used by people who have not previously installed security software on their PCs.
However, Alex Kochis, director of Microsoft's Genuine Windows team, said in a blog post that Security Essentials will work only with legitimate copies of Windows.
Computer users running pirated copies of Windows will not be able to run the software, but will instead be offered the chance to buy a legitimate copy of Windows.
Microsoft has a mixed relationship with the large number of people who pirate its operating system. The company blocks many of its applications from working with illegal copies of Windows, and has launched several atempts to sue pirates.
However, Microsoft does allow security updates to be sent to pirated copies of Windows and Internet Explorer. The company has said that it does not want unprotected PCs to host viruses and make the work of computer criminals easier.
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