When you try to install a Windows Live program, for example, Windows Live Messenger, the Windows Live Essentials installation fails with following error code 0x80070643. This issue occurs because a previous installation puts the computer in a state where a restart is pending.

To resolve this issue, restart the computer, and then reinstall Windows Live Essentials.

  1. Restart the computer
  2. Visit the following Windows Live Web site: http://explore.live.com
    Or http://explore.live.com/windows-live-essentials-beta for
  3. Windows Live Essentials Beta

  4. Click the Download button. When the file download dialog box pops up, click Run to start the Installation Wizard
  5. Reinstall Windows Live Essentials