Hi Jeet,
Thanks for your support.
I have tried hard reset but there is no change - printer blocks on the very beginning of its start up (HP logo and frozen progress bar on the screen) and after few seconds the screen shows "error code 0XB83941FC".
I can't do anything because it blocks almost immediately upon pressing "on" button. Once stacked nothing else is possible but to remove electricity cable thus causing its switching off.
I've tried four-five times hard reset (without and with USB cable being connected) but resultless every time.
P.S. Before "update" three-four days ago the printer was OK and working in wireless mode. Update has started and was made automatically, without my interference at all.