Microsoft Windows Update error code 8024400a: Computer Freezes when checking for Windows Update. Getting Error code 8024400a when upgrading to Windows 10 from Windows 8.1.When you try to download or install updates from Windows Update in Windows 8, Windows 7, Windows 10, or Windows Vista, the computer may freeze. If the computer freezes during Windows installation, it might be due to error code 8024400a.