Windows 10: Win7 key to reboot Win10

My PC used to run Win7 when I bought it few years ago, upgraded it to Win10 later as it was free.

I would like to reboot my windows 10 now but do I use my old Win7 product key to reinstall Win10? or is the key no longer usable at all?

:)

 

Hello, can I use the win10 key to activate mny win7?

Btw, does the program u suggested me detect only the win7 key (if there is) or it should detect the win10 key as well?

Also, I upgraded from win7 to 10, so doesn't it count as "u can downgrade to win7"?

 

Built new computer, running unactivated Win10 Home, have Win7 Pro key

I was initially thinking of buying a Win10 Home key, but I realized I still have a Win7 Pro key I purchased that I have never upgraded to Win10 and is not currently in use.

Two questions

• Can I use the Win7 key to activate Win10 (or is that no longer an option)
• Will Win10 Home turn into Win10 Pro (assuming I can still use key)

 

Win7 to Win10 - Product key question

I'm just wondering if the product key I purchased years ago for Win7 will still be valid if I reserve Win10 and install it?

Say for example I want to have Win7 on my main studio PC (as I know all my DAWs and VST plugins work on there perfectly), but also run Win10 on my other machine, would that be possible from the same key? Or would I void the Win7 key as soon as I reserve
and install Win10?

I rely on Win7 for work, so the last thing I want is to void my key for it.

I often reformat my system and I'd hate to do so then find out my Win7 key no longer works...

Thanks in advance!