John & Jane Doe wrote:

This is what the Magical Jelly Bean Keyfinder found for Windows:
https://s9.postimg.org/vn6cj888f/key_windows.jpg

Windows 10 Pro 20-digit product id which says "match to CD Key data".
CD Key: 25-character key
Computer Name & Registered Owner

Magical Jelly Bean Keyfinder found the generic Win10 key used for the free
upgrade and stored in the registry on the device *after* the Windows 7
genuine license was verified during the free upgrade process.

i.e. you don't have a Win10 Product key. The same generic key is used on
all machine. You do have a device with a digital license and most likely
can be clean installed with Win10 version 1511(10586 your version), version
1607(14393 later build than yours) media and possibly 1703(build 14393) media.

If you clean install using the generic key it will not activate. You would
subsequently need to provide a valid Win10, Windows 7(OEM or retail) product
key to activate.
- i.e. if you clean install you should choose the 'Skip' product key
option(Do not enter the generic key the 'Keyfinder' found) and let Win10's
clean install setup activate using the digital license stored on the server.

You're fortunate that the original owner didn't activate and link a
Microsoft account to the digital license.
Windows 10/Setttings/Windows Update/Activation
If so, when looking on the Activate screen it would have said "Windows is
activated with a digital license **linked** to you Microsoft account"

Finally, if this machine(unlikely since its 2009 vintage Windows 7 Home
based on your feedback) it does not have a Windows 7 Home product key on
embedded on the bios. If it did and you clean install, Windows 10 Home
would be the default installed o/s.

How did the Windows 7 Home get to Windows 1o Pro ?
Three ways.
- the prior owner upgraded Windows 7 Home to Pro using a Windows 7 Pro key
or
- the prior owner upgraded from Windows 10 Home to Pro using a valid
Windows 10 Pro key
or
- the more likely, the prior owner took advantage of the Windows 7 to
Windows 8 Pro upgrade offer, then used the free Win10 upgrade to upgrade
Win8 Pro to Win10 Pro.

One final note: Since this is originally an OEM machine, it falls under the
rights that allow transfer of the machine and license to another owner
Win10
"a.Software preinstalled on device. If you acquired the software
preinstalled on a device (and also if you upgraded from software
preinstalled on a device), you may transfer the license to use the software
directly to another user, only with the licensed device. The transfer must
include the software and, if provided with the device, an authentic Windows
label including the product key. Before any permitted transfer, the other
party must agree that this agreement applies to the transfer and use of the
software."
i.e. their should be a sticker on the machine that has the Windows 7
Product key.

Fyi...if not already answered, you can change 'her' name by editing the
registry key that contains the registered owner name.

--
...winston
msft mvp windows experience 2007-2016, insider mvp 2016