If you’re planning on doing a re-installation of Windows, it’s a good idea to make a backup of your product key. If the Certificate of Authenticity has become unreadable due to wear and tear and you don’t have a note of it anywhere else then this simple script will tell you what your product key is.
Copy the following script into notepad:
Save this as productkey.vbs ensuring that you change the “Save as type” to “All Files”.
Then run this script by double clicking it, a popup window will reveal your product key.