Windows 10: Recovering Windows 10 Pro activation key

I purchased an upgrade from Windows 10 Home to Windows 10 Pro three years ago. I still have the email with the order confirmation number in it and can see the order in my order history, however the email does not contain the Windows 10 Pro product key and the store order just has a broken image and the "Windows 10 Pro" text itself gives a 404 error when I click it. I recently re-installed Windows 10 and need that key to upgrade.


Existing Microsoft documentation has been entirely unhelpful. Support is apparently off for the holidays. Any suggestions?

:)

 

Windows 8.1 pro + WMC key activation

This worked for me last time with a Win 8 key.

Install Windows 8.1 and enter KMS key during setup. Once in windows change product key to my Windows 8 key. Go to add features and enter my WMC add-on key. Drink a beer to a job well done.

 

Windows 8.1 pro + WMC key activation

So it will be fine installing 8.1 pro with a KMS key, then switch to my 8 pro key and it will activate ok?

Maybe a daft question but why can't you just install 8.1 pro with the 8 pro key, or is it different keys for 8 and 8.1? seems silly when 8.1 is a free update anyway.

 

Windows 8.1 pro + WMC key activation

I was considering buying a WMC pro add on for my windows 8.1 pro install, but have googled and found some people had trouble activating it. Has anyone on here got any experience with this.

As to my install, I have a real Windows 8 pro key. So I installed windows 8 pro using a MSDN retail .iso which was activated soon as it finished installing , then I updated to .1 pro.

When you buy the WMC add on, it changes your key, I have read some people have had trouble activating it, now mine activates from windows, I hate doing the phone activation crap, so I don't want to have to do that after the WMC add on finishes installing.

The question is, what happens to my windows 8 pro key, is it still usable? and how would i go about if I had to reinstall? would it have to be-

Install win 8 pro-update to 8.1-install WMC add on, or could i use a windows 8.1 pro with WMC disc?

Thanks guys

Tigger