Windows 10: I have a legitimate windows 10 product key, but I can't activate.

I got a windows 10 key from an old computer that I bought new. Whenever I try to use it on my new computer, I always get the same message, "The product key that you entered didn't work. Check the product and try again, or enter a different one. 0xc004f050". I don't know what's going on, so any help is appreciated.

:)

 

Windows 10 will not activate Error code 0x803F7001

thanks
I activated my Windows 10 from product key Windows 7

 

Activate windows 10 after re-installing (I have lost my product key)

I own a Lenovo T430 laptop. In 2017, I installed Windows 10 using my original Windows 7 product key. Unfortunately, I cannot find that product key anymore. I need to re-install windows 10. Will it be automatically activated after the installation, if I skip the step of asking the product key during the installation?

In my opinion, I believe that my laptop will have a digital entitlement stored on the Microsoft Activation Servers and this will not be a problem. Is that true?

If not, please suggest me a solution or a workaround.

 

my windows 10 oem didn't come with a product key

windows 10 can also activate solely based on HWID no key required how do you think the microsoft store activation works it installs a generic key and activates based on hwid