Thank you for the advice. Unfortunately, once the closing down screen appears, my mouse becomes inoperative as does the keyboard, so I can't "Ctrj+Alt+Delete".
The problem exists even if no program has been running, ie shutting down immediately once the system settles after switch on.
My Toshiba laptop hangs when close down selected - normal display, "closing down" on screen. It could be the result of a recent update, but the restore facility relies on a normal shutdown.Any assistance would be appreciated.