Microsoft has recently announced estimative statistics on the performance of its Windows Validation Tool. According to the data, no less than 60 million machines running copies of WGA have failed the tool's validation since its starting implementing the anti-piracy utility. The controversial tool that many regarded as spyware and that even attracted two class action suits, steered further controversy when the users whose operating system were deemed pirated claimed that they were actually running genuine versions of Windows.

The Redmond Company has indeed confirmed the existence of selective false positives. The software giant stated that the false positive cases were only isolated incidents triggered by data entry errors, and that it had made all the necessary adjustments in order to avoid additional erroneous reports via the anti-piracy tool. Microsoft detected the effectiveness of WGA, claiming the all the false positive incidents combined represented a mere fraction of a percent of all the 60 million identified illicit copies of Windows.

"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," stated Alex Kochis, a licensing manager on the WGA team claiming that outside of the small number of errors, all the copies of Windows OS discovered as illegal were actually infringing in some way on Microsoft's licensing policy.