Product keys are needed to activate Windows
Without the 25 character activation code you will be unable to activate Windows and it won't function. Codes come from all sorts of sources including digital downloads, and developer subscriptions and software provided by original equipment manufacturers (OEMs). The technology was introduced in an effort to reduce software piracy back with Windows XP. It is perfectly legitimate to re-install and re-activate Windows on the PC for which the product key is eligible as often as you like.
"Most licenses allow for software to be re-installed and activated on the same PC an unlimited number of times. To ensure that you are using your license properly, please see your end user license agreement or product use rights for details on a specific product."
Edition of Windows
The code is also responsible for determining what particular edition of Windows you are eligible to run on your computer.
Original product keys stored in your computer
This article is concerned with codes stored in your PC, which might be useful if you are reinstalling from scratch or upgrading to a newer version of Windows and need the original product key from a previous version.
TL:DR – Product keys are often stored in the Advanced Configuration and Power Interface (ACPI) BIOS settings of computers to aid with reinstallation without costly support calls for the original hardware vendors. This is memory which is for configuration information and is separate from the drive on the system. It is easy to fish the information out if you know the commands needed.
Contents
Command to display your original product key
Linux
If you have installed or booted from a Linux distribution you can try the following commands, which display the original product key.
$ sudo apt install binutils
$ sudo strings /sys/firmware/acpi/tables/MSDM
[sudo] password for youraccount:
MSDMU
COMPUTERMFR
XXX
XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
Windows
If you are running Windows 10 you can use the following command to return the original product key
C:\> wmic path softwarelicensingservice get OA3xOriginalProductKey
XXXXOriginalProductKey
XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
References
See also:
