Planning for Windows Product Activation

Planning for Windows Product Activation

Windows Product Activation (WPA) deters piracy by requiring your Windows Vista installation to be activated. Product Activation is based on requiring each unique installation to have a unique product key.

WPA ties your Product Key and Product ID to your computer by creating an installation ID. The installation ID is made up of your Product Identification (PID) and a computer identifier, called a hardware ID, or HWID. The installation ID is sent to a Microsoft license clearinghouse, which verifies whether Microsoft manufactured that PID and that the PID has not been used to install the operating system on more hardware than is defined by the product's License Terms. For Windows Vista, the License Terms state that you can install on one computer. If this check fails, activation of Windows Vista fails. If this check passes, your computer receives a confirmation ID that activates your computer. After Windows is activated, you never need to perform Product Activation again, unless you significantly overhaul the hardware in your computer. You must activate your installation within 30 days after installing Windows Vista.

If the Product Key is used to install Windows Vista on a second computer, the activation fails. Additionally, if WPA detects that the current installation of Windows Vista is running on a different computer than it was originally activated on, you must activate it again. In this way, WPA prevents casual copying of Windows Vista.


WPA is not required under volume-licensing agreements.

For unattended installations that are not performed using volume-licensing media, a separate answer file, including a unique Product Key, must be created for each computer on which Windows Vista is installed.


Because Product Keys cannot be determined from within the system, it is recommended that you create a database that lists each computer and the Product Key that corresponds to its installation.