Secondary license not working?

I am trying to install Windows 10 on a new PC for a friend of mine. She bought a secondary licence of Windows 10 Pro, but the key just doesn't work.
Not even the setup recognizes it, giving me "We couldn't verify the product key. Please check your installation media" error.

When I try to activate it post-installation, I get these errors:


apparently it's a Dell OEM licence but that shouldn't matter, should it?

The most bizarre thing is I managed to activate it on my own PC right away.

What the hell is going on here?

Hmm that could be.
I'll have to try to argue with the shop the key was bought in, yay...

- - - Updated - - -

BUT why did the key activate on my own PC then?

I'm sure I activated plenty of secondary OEM keys back in Windows 7 times. This makes no sense.

Samuria said:

If its activated on your pc then you have used the licence so it cant be used again

Did you even bother reading all my posts? I did that as a test AFTER it didn't work on the PC it was intended for.

- - - Updated - - -

This is precisely what my friend bought.
Looks like there's no shortage of them on the internet.
Windows 8 Pro / 10 32/64bit Product Key Dell JN38V Pc0xy for sale online | eBay
This looks like a package that wasn't used before. She said it was sealed.

Installation media is identical for ALL editions, you just select whichever you want.
Yes I was installing Pro. Obviously, duh.

Octopuss said:

Installation media is identical for ALL editions, you just select whichever you want.
Yes I was installing Pro. Obviously, duh.

Hi there
Not sure of the exact problem here
Please expain

1) has this key EVER activated on a PC whether yours or another PC
2) If yes - then it can't be used on another PC - period - end of.
3) If no then you have a valid case for refund / call Ms activation centre and get activation over phone. - however to get a digital license you need at least to create an Ms account (you don't have to use an Ms cccount to logon to windows if you set it up as a local account)

If you have old W7/W8/W8.1 system then the "Free upgrade" is still working believe it or not so that's another route to try.

Cheers
jimbo

I specifically wrote it was sealed. So no, it shouldn't have been activated before.

Phone activation for Windows 10 was removed at some point in past (probably last year I'm assuming).
Since the key is supposedly for W8 and W10, I tried installing W8.1 and it refused to activate too, so the key is definitely bad. I have no idea why though. I've never seen anything like this.