How to troubleshoot a blank Windows Device Manager?
Why does this happen? It happens if the Plug and Play Service is not enabled.
The Fix for this issue is very simple:
Go to the Start button – Open the Run Dialogue Box – Type in services.msc in it – right-click or double-click on Plug and Play – Select Start – and then Click Apply / OK.
Remember, the Startup Type for this Service must be Automatic.
Close the Services.msc window and restart your computer for the changes to take effect.