What is: "Preparing to configure Windows. Don't turn off your computer"

Hello,

Is the recent startup message I received: "Preparing to configure Windows. Don't turn off your computer" a hack, malware or Trojan Horse?

I pulled the plug and restarted in safe Mode with networking - received same message, pulled plug.

I'm running Windows 7 on a Dell Optiplex 755.

Can't imagine Microsoft wants to update my computer.

Thanks