Recently I've been hearing questions from journalists, other bloggers and customers about what exactly makes systems fail validation. Specifically, I have been asked for two things. First, a breakdown of the kinds of piracy that are detected by WGA and which are the most common. And second, what is the rate of ?false positives? with WGA (falsely identifying a copy of Windows as counterfeit)? First on the question of what makes up the WGA failures. About 1 in 5 of the 300 million PCs that have run WGA validation fail. That is pretty much in line with industry numbers for software piracy. By volume most of the validation failures detected by WGA are a result of installs that use a stolen volume licensing key. Using stolen volume license keys has been a well known method of counterfeiting Windows XP for a while. This accounts for around 80% of the failures today. As an example, one stolen license key from a US university ended up on over a million PCs in China. The rest of the failures are caused by a mix of other types of counterfeiting and piracy, including a variety of forms of tampering, hacking and other forms of installing unlicensed copies. Sometimes people try to hack Windows Product Activation itself (often not totally successfully either) and other times people try to modify files to prevent XP from needing to activate at all. Some failures are caused by improper attempts to install or repair software on an otherwise genuine PC. All of these activities will result in WGA validation failures and they should.

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