can i activate windows 10 again used product key

[Pucchu_1]

sir i have a problem with my new lenovo G50-80 5th generation laptop comes with windows 10 home single language,this laptop is running to much slow after using 10 days i want to format this laptop but my main question is can i activate windows 10 again and also i don't have product key but i founded windows 10 product key through keyfinder.can i activate windows 10 again through founded product key from laptop and also don't have windows 10 setup but i downloaded windows 10 home single language from internet.can i activate windows 10 again through product key.

 

[AmusingUserID]

You don't need the key, windows 10 remembers the hardware and activates it that way

Just use media creation tool and make image on usb stick, do a fresh install and it will activate itself

 

[Dark Lord of Tech]

http://windows.microsoft.com/en-us/windows-10/activation-in-windows-10
Activation in Windows 10




You bought a new device running Windows 10.


Product key

(Pre–installed on your device, included with the device packaging, or included as a card or on the Certificate of Authenticity (COA) attached to the device.)