http://www.theinquirer.net/inquirer/news/1562900/microsoft-denies-windows-door
A MICROSOFT SPOKESVOLE has denied fears that the US National Security Agency (NSA) placed surveillance technology into Windows 7.
The worry is that if the NSA was involved with the development of Windows 7 it might have put "backdoors" into Microsoft's code that would help it track users and intercept users' communications.
Since no one outside Microsoft except a few secretive government agencies and very large corporate customers can review its Windows 7 source code, most people simply have to take the Vole's word that there are no intentionally built-in security holes in it.
How about unintentionally ?