Windows 10: can I activate win 10 after reinstall it from win 7?

Can I activate win 10 if I reinstall it from win 7?

:)

 

Win 7 and Win 10 on network

I have home network with separate modem, router, and WAP's. My Windows 7 computer does NOT list the Windows 10 computers on network computer list but the Windows 10 computers network list DO list the Windows 7 computer.

Turned off firewalls, gave permissions, shared drives. Nothing allows Win 7 computer to access the Win 10 computers.

Any suggestions for a fix?

 

How to reinstall Windows 10 if my computers used the free upgrade from 7 and 8?

1 of my laptop has win 7, but not ufei so the key is not in the bios, but I did use the internet after I upgraded to win 10, so it's safe for me to just wipe and reinstall win 10 with win 7 key?

seems like my win 8 machine will be fine with the ufei thing.

 

Activated Win 7 correctly yet fail to actiavte Win 10

I registered the Win 7 key got a message saying that I have indeed activated Win7.

So I got the icon in the corner and registered a copy through it.

I neede Win 10 because Skylake doesn't work nicely with Win 7.

So I installed win 10 using Media Creation Toolkit.

but upon installing Win 10 and trying to activate it, I got an activation error.

The only machine using that copy of Win 7 is the current one.

So I rolled back to Win7, looked if there was something that I messed up,

but it still says my product key is correct and I am an activated user.

Any solution suggested by Microsoft Help doesn't work because

I already am ACTIVATED.

So solutions? I am currently using my computer without a mouse because USB ports don't work on

Skylake and Win 7 combination.