Activate your Windows 10 license through a Microsoft Support Number
Microsoft still includes product activation in Windows 10 to prevent theft. Windows 10 includes a new convenient Microsoft Submar option for product activation. If you upgrade from an active Windows 7 or Windows 8.1, Windows 10 will be activated automatically. If you are transferring a Windows 10 license to a new computer and you have an Internet connection, you can use the Microsoft Support phone number to activate it.Activate Windows 10 using Microsoft Support
After installing Windows 10, press Windows key + R, then type slui then press enter on your keyboard.
This action will launch the Activation Wizard. Select your country or region and click Next.
Then on the installation ID screen, you will have to call the Microsoft Number listed on the screen + 1-800-201-4243.
Update: In Windows 10 Creators Update and later versions, contacting support is now available in a new app called Get Help or you can use a web browser to contact support using a virtual assistant.
How to activate your Windows 10 license through Microsoft support number
If you are transferring a Windows 10 license to a new computer or you need to reactivate your Windows key, here is my experience using Microsoft Support.