Power off completely after shut down your Computer.

• First click on Start button then type Regedit in Run option.
• Here locate the location to:

        HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon

• Here in right side panel, double click on PowerdownAfterShutdown and set its value 1 to power down.
• Now close the registry editor and restart your computer after any changes to go into effect.