To Activate Windows 8.1 by Phone
2. Press the Windows + R to open the Rusluisn dialog, type slui.exe 4, press Enter, and go to step 7 below.
3. Open an elevated command prompt, type slui.exe 4, press Enter, and go to step 7 below.
4. Open the Power Users Tasks menu, click/tap on System, and go to step 5A below.
5. Open the Control Panel (icons view), and click/tap on the System icon.
6. Open PC settings, click/tap on Activate Windows on the left side.