Product activation is a license validation procedure required by some proprietary computer software programs. Specifically, product activation refers to a method where a software application hashes hardware serial numbers and an ID number specific to the product's license (a product key) to generate a unique Installation ID. This Installation ID is sent to the manufacturer to verify the authenticity of the product key and to ensure that the product key is not being used for multiple installations.
As a trial, Microsoft first used product activation in some versions of Microsoft Office 2000. Some copies sold in Australia, Brazil, Canada, China, Hong Kong, New Zealand and the United States required the user to activate the product via the Internet. After its success, the product activation system was extended worldwide and incorporated into all subsequent versions of Windows and Office. This practice has become a subject of debate, primarily because it was one of the first widespread uses of a product activation system in a general consumer product.
An 'unactivated' product usually acts as a time-limited trial until a product key is purchased and used to activate the software. Some products allow licenses to be transferred from one machine to another using online tools, without having to call technical support to deactivate the copy on the old machine before reactivating it on the new machine.
