2.Enter add features in the search box, and then tap or click Settings.
3. Tap or click Add features to Windows 8 and then do one of the following:
Follow the steps to purchase and enter a product key.
4.Enter the exact product key which you used during WMC installation on Windows 8.Click Next.
5.Select the check box to accept the license terms, and then click Add features.
6.PC will restart automatically and Windows Media Center will be available for use.