Produkey Using External Drive

my 16 month old hp pavillon laptop died it had win 10 pro and office 2016 pro installed
have the old drive connected on a desktop, comes up as d:
when I point produkey to d:\windows it returns nothing

running produkey myself, I am an admin:
if I point it to D:\Windows\System32\config\system (or any other hive chunk). it returns:
"error 1314 a required privilege is not held by the client"

if I run produkey as admin and point to same as above it returns:
"error 19 the media is write protected"

so I have a catch22 thing, any ideas to get around this conundrum?

 

thanks, however my drive is not encrypted. or is it that the hive chunks alone are encrypted?
and windows keeps some encryption key for them associated from the user id, something like each used id has an encryption key somewhere so that when you login to windows it uses that 'user key' to set up the registry for that account?

and now just wondering why would produkey would need write permissions for registry stuff?

 

Here they describe using a Linux boot disk to copy the hive off then using produkey.
https://www.howtogeek.com/64600/how-to-recover-windows-and-software-keys-from-a-broken-computer/