Two ways to change product key on Windows 10
Use Slui to change the Windows Product Key
Enter Slui into the Search box on the Start Menu or Search Bar in the Taskbar and press Enter. Click Yes if the UAC notification window appears.
Next on the Enter a product key dialog, enter a new product key and click Next to change the product key.
Use Command Prompt
First, open the Command Prompt under Admin. To do this, enter the CMD into the Search box on the Start Menu, then press Ctrl + Shift + Enter to run Command Prompt under Admin.
If the UAC prompt appears on the screen, click Yes.
On the Command Prompt window, enter the following command and press Enter to update the Windows 10 Product key on your Windows 10 computer:
Note, in this statement, replace your windows 10 product key with your Product key.
For example, if your Windows 10 license has a Product key of 11111-11111-11111-11111-11111, enter the slmgr.vbs / ipk 11111-11111-11111-11111-11111 command into the Command Prompt window and press Enter. .
After changing the Product key, the next step is to enter the following command into the Command Prompt window and press Enter to activate Windows.
Wait for execution command completed.
The last step is to check whether the new Product key is enabled on the System Properties window.
To do this, first open Control Panel => System and Security => System. On the System window, you will see the Windows is activated message along with the Product ID in the Windows activation section.