You may have encountered a problem where you need to format a Windows PC but don't have the Product Key. But you don't know the password of the local admin (because of a number of excuses).
If you fortunately have a Live Kali DVD you can boot into, you can try using the chntpw application:
To look into the relevant registry file mount the Windows disk and open it like so:
chntpw -e /path/to/windisk/Windows/System32/config/RegBack/SOFTWARE
Now to get the decoded DigitalProductId enter this command:
Now to get the decoded DigitalProductId enter this command: