oops - sorry, Step 2 took quite some time with multiple messages - in case they are helfpful:
update was installed successfully, restart required
after restart, computer displayed 'configuring windows updates, do not turn off your computer'
computer restarted and displayed 'preparing to configure windows, do not turn off your computer'
then displayed 'configuring windows updates, do not turn off your computer'
then displayed 'failure configuring windows updates reverting changes, do not turn off your computer'
then displayed 'shutting down'
computer restarted and displayed 'preparing to configure windows, do not turn off your computer'
then displayed again 'failure configuring windows updates reverting changes, do not turn off your computer'
windows started normally after that
cbs log attached