Can i use the OEM key on new windows installations on other machines? [duplicate]

I have used my university educational Windows licence (from Microsoft Imagine/Dreamspark: different names for the same thing) on my custom built computer, but now I would like to sell the computer, but I wish I could sell it without my Windows licence. The problem is, Windows is auto activating each time I reinstall it. Even if I remove key with slmgr /upk command (https://www.google.com/amp/s/www.howtogeek.com/124286/how-to-uninstall-your-windows-product-key-before-you-sell-your-pc/amp/), it is removed but only until I reinstall Windows again.

It is hard to find information about my problem in the Internet, because almost everyone wants something opposite - to have Windows activated after reinstall. Does anyone know what I can do now?

The Digital License never really goes away on that PC for the rest of its life. The new owner will be able to install the same version of Windows 10 on it, and it will activate with the digital entitlement. There's nothing you can do about it, as that's Microsoft's problem.

If you bought the computer with an OEM license (meaning Windows originally came with the computer), then there is no point in removing the key. As far as Microsoft is concerned, this key goes with the computer, and only with this computer.

If you bought a retail license of Windows 10, you will be able to install it on another PC. Microsoft will just make an allowance for an additional install.

If indeed you have a retail license of Windows 10, it might be safer to uninstall the key with slmgr /upk and turn off the computer until after you install and activate it on the new computer and before selling the old one, just in case.

Any problem that you might have with activating a retail key is best solved by calling Microsoft Support. But they will not answer a problem with an OEM key.