registry decoded

Devices that are installed but are not currently connected to the computer (such as a Universal Serial Bus (USB) device or "ghosted" devices) are not normally displayed in Device Manager. This tweak causes all devices to be shown.

Open your registry (press win+r and type regedit , hit enter )
goto

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\
Environment]


Create a new String value(right click on environment -> new -> string value), or modify the existing value called 'DEVMGR_SHOW_NONPRESENT_DEVICES' using the settings below.

set it's value to 1

Exit your registry, you may need to restart or log out of Windows for the change to take effect.