Windows 10: Windows pro activation key

I have purchased a second hand laptop and have had my harddrive placed in the new devices, sadly all of a sudden my windows pro is not activated it was working fine on my old device which I have had for 6 years - I have had a few moves and a lot of trauma in my life and with this stupid virus and not working I can't spend the money on a new one - i I can not find an activation key anywhere - I dont want to lose any of the programs that I have on my device either - HELP

:)

 

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