Windows 10: reinstall windows 10 - why do I need the product key

My old laptop Dell XPS 15 crashed and I had to purchase a new mSata drive and reinstall Windows 10 with the Windows Media creation tool.A. Before, it was possible to select Windows 10 Pro from a list, but now only Windows 10 is selectable, and Windows 10 family was installed instead of Pro.B. I was under the impression that the product key was saved in the bios but this doesn't seem to be the case since I'm told my windows is not activated.C. Is it not found because I disabled secure boot in the bios?I had to set the boot options to Legacy instead of UEFI in the bios, since I was tasked to c

:)

 

Reinstall Windows 10 with OEM product key

When you upgraded from a previous version of Windows or receive a new computer preinstalled with Windows 10, what happened is the hardware (your PC) will get a digital entitlement, where a unique signature of the computer will be stored on Microsoft
Activation Servers. The Windows 7 or Windows 8 genuine license you were previously running will be exchanged for a diagnostics key.

Anytime you need to reinstall Windows 10 on that machine, just proceed to reinstall Windows 10. It will automatically reactivate.
You will prompted to enter a product key a couple times through the installation, click I don't have a key and Do this later.

There is no need to know or get a new key, but if you have issues with Digital Licensing or the Activation Troubleshooter, you can utilize an existing Windows 7 or Windows 8/8.1 product key
you already ownto reactivate if necessary. or use the reset function in Windows 10.

Step 1: How
to download official Windows 10 ISO files

Step 2:

• How to: Perform a clean install of Windows 10

 

Windows 10 Product Key

Hi Oscar,

Since the laptop has no battery compartment wherein the product key is usually located, we recommend that you follow these steps to find your Windows product key:

• Press Windows + X and select Command Prompt (Admin).
• Enter this command: wmic path SoftwareLicensingService get OA3xOriginalProductKey
  and hit Enter.

Also, if you're looking to reinstall Windows 10 after a hardware replacement, we recommend that you follow the steps provided in this

article.

Let us know if performing these steps resolved the issue.

 

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

Will windows 10 still accept the license keys from 7 and 8 now if I reinstall my computer?

Does Microsoft keep a list of users who upgraded to Win 10 using their 7 and 8 keys so that when users need to reinstall windows 10 the old keys would work?

Do I need to call in Microsoft to ask them to activate my Windows 10 when I give them my win 7 keys?

Both computers are laptops. The windows 7 machine had the serial printed on the back, and I needed to enter that when I upgraded to 10. The windows 8 machine had the serial built in inside its boot system so I didn't need to enter the key when I upgraded to 10, but I did manage to write down the keys using a fetcher program.