Windows 10 Professional / Home

          1. Press the Windows key/logo, go to Settings > Update and Security > Activation.



2. Click the Change product key.

3. Enter your product key, then click the Next button.

4. Click Activate.



If you prefer clean installation, please refer to How to perform Windows 10 Clean Installation.




Windows 7 Professional

          1. Select the Start button, right-click Computer, select Properties, and then select Activate Windows now.





2. If Windows detects an internet connection, select Activate Windows online now.  You might be asked for an admin password or to confirm your choice.



3. Enter your Windows 7 activation key when prompted, select Next. Activation will start. This might take a few minutes. 



4. Once done, it will say Activation was successful, click Close. At this point, you can go back to Properties and scroll down to Windows activation, it should now say Windows is activated.




If you prefer clean installation, please refer to How to perform Windows 7 Clean Installation.


Note: In case you need a Windows 7 ISO, please proceed here




Windows 8.1 Professional


1. Select the Start button, type PC settings, and then select PC settings from the list of results.


2. Choose Activate Windows.


 

3. On the Activate Windows screen, click Enter key.


 


4. Enter your Windows 8.1 product key, select Next. At this point, just follow the on-screen instructions to activate Windows 8.1.




If you prefer clean installation, please refer to How to perform Windows 8.1 Clean Installation.


Note: In case you need a Windows 8 ISO, please proceed here



Congratulations! Your Windows is now activated!