Unable activate Windows 8

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Unable to Activate Windows 8.


  1. You upgraded to Windows 8, but didn't have a previous version or the correct edition of Windows installed.

  2. One copy of Windows might have been installed multiple times (if Windows 8 is migrated to Mac using Parallels).


Please use the following steps to fix Windows 8 Activation issues:

  1. Go to Search and type in regedit, hit Return/Enter

  2. Navigate to HKEY_LOCAL_MACHINE/Software/Microsoft/Windows/CurrentVersion/Setup/OOBE/

  3. Change MediaBootInstall from 1 to 0

    select the item "MediaBootInstall", double-click on it, then you can type in '0' as the value, (hexadecimal or decimal).

  4. Go back to the Start screen (Search) and type in cmd

    Note: To get back to the Windows 8 start screen, you just hit "COMMAND" key on your Mac keyboard

  5. Right-click Command Prompt and select to Run it as Administrator

  6. Type in the following command:

    slmgr /rearm 

    and hit Return/Enter.

    Exit out of the command prompt window.

  7. Reboot Windows Virtual Machine

  8. Go to:

    Control Panel > System and Security > System > Windows Activation and check if Windows 8 has been activated.

Please note that the isssue with Windows 8 activation is not related to Parallels Desktop directly.

If the issue still persists, please contact Microsoft Technical Support.

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