Windows 10: Product Key Activation for second hand laptop?

I got a notification on my acer laptop touchscreen saying the windows 10 enterprise licence will expire soon and that I need a product key or something. I tried looking for ways to find the product key, but this is a second- hand laptop, I didn't receive the packaging or anything with it, so I'm not sure what to do ;-; I can't ask the person who gave it to me either. Is there a different way to activate it?

:)

 

product key on second-hand laptop - can i use it?

I have purchased second-hand Lenovo laptop from ebay. There was no OS installed, but there is Windows 7 Pro COA sticker with product key. Can I legally use this product key? Can I install Windows 10 and activate it with this product key?

Thanks.

 

I bought my laptop second-hand and don't have a product key

I bought my laptop second-hand and don't have a product key ho do i get a new one

 

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.