Windows 8 upgraded to Windows 10, factory reset back to 8, can I install Windows 10 again?

[tow2guru]

HP desktop was sold with windows 8 on it. Parents had it upgraded to Windows 10 when it was free. Something happened to the desktop and became unusable "in their eyes". They bought a new computer. This Windows 8 machine now with Windows 10 had to be recovered using original settings. So, now it has Windows 8 back on it and Windows 10 isn't free anymore. Can I reinstall windows 10 for free? or because of the factory reset, I now have to purchase it.

 

[USAFRet]

HP desktop was sold with windows 8 on it. Parents had it upgraded to Windows 10 when it was free. Something happened to the desktop and became unusable "in their eyes". They bought a new computer. This Windows 8 machine now with Windows 10 had to be recovered using original settings. So, now it has Windows 8 back on it and Windows 10 isn't free anymore. Can I reinstall windows 10 for free? or because of the factory reset, I now have to purchase it.

If it had been fully upgraded to Win 10, and it was actually activated, you should be able to just do a full wipe and reinstall of Win 10.
Create your own USB or DVD here: https://www.microsoft.com/en-us/software-download/windows10
When it asks for the license key, Skip. It should, in theory, activate once the system goes online.