Brian Livingston (full disclosure: My "Windows Vista Secrets" co-author) this week revealed that Microsoft includes a simple registry key in Windows Vista that allows users to postpone product activation almost indefinitely. Normally, an installed version of Vista would have to be activated within 30 days. After that time, the OS slips into a reduced functionality mode.

Livingston charges that product activation was designed almost solely to prevent individuals from installing a single copy of Windows on more than one PC, and does nothing to prevent mass piracy. He notes that the Vista version of product activation is even less effective than the version of the technology used in previous Windows versions, and could result in unscrupulous PC makers unleashing unlimited numbers of pirated versions of Vista on unsuspecting customers.

What's interesting about the technique that Livingston documents is that it's not a hack or exploit, but rather utilizes a publicly-known Vista registry key that Microsoft documents on its support Web site. Changing the value of this key, users can extend Vista's activation countdown by 30 days, and it would be easy to automate the process, ensuring that the countdown was reset regularly, so that the PC would never need to be activated.

Livingston investigated the key and discovered that it's included in Vista so that Microsoft's biggest corporate customers can work around onerous new volume licensing requirements that require them to set up special servers for managing product keys. This policy was put in place to prevent the kind of volume license key abuse that occurred during Windows XP's life time, Microsoft says.

If you're interested in reading more about this, please refer to Livingston's write-up in the Windows Secrets newsletter.