When searching for undocumented commands on the Panasonic Ultra-BD player DP-UB242 in inadvertently activated a "lock" mode. Now the player refuses to eject the tray (both from remote and the button on the device), instead the LED blinks twice. So I assume that it is a restricted (dealer) mode, for allowing customers to play but not to change or steal the disc in the player.

Anyone knows how to get out of this mode? Of course, I have already tried the system initial reset.

I found this out there, have you seen/tried this (can't hurt):
Eject lock:
With the unit powered on, press and hold stop button and power button on main unit for at least three seconds until it shows unlocked.
Function lock:
With the unit powered on, press and hold play button and power button on main unit for at least three seconds until it shows unlocked.

Thanx for the suggestion. Unfortunately, the said model neither contains a display nor any buttons on the device (except power and eject)...

I found the solution later: It turns out that sending the IR signal Panasonic 176.1 91

0000 0070 0000 0032 0080 0040 0010 0010 0010 0030 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0030 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0030 0010 0030 0010 0010 0010 0030 0010 0030 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0030 0010 0030 0010 0010 0010 0030 0010 0030 0010 0010 0010 0030 0010 0010 0010 0010 0010 0030 0010 0010 0010 0030 0010 0010 0010 0030 0010 0030 0010 0030 0010 0ACD

resets the player to delivery state, including freeing the lock.

FWIW, the signal to lock the player, if anyone wants it, is Panasonic 176.0 251
0000 0070 0000 0032 0080 0040 0010 0010 0010 0030 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0030 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0030 0010 0030 0010 0010 0010 0030 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0010 0030 0010 0030 0010 0010 0010 0030 0010 0030 0010 0030 0010 0030 0010 0030 0010 0030 0010 0030 0010 0010 0010 0030 0010 0010 0010 0010 0010 0030 0010 0010 0010 0ACD

Hi i know this is a bit old but my player seems to have the same lock problem how did you upload that hex code to the unit? A IR transmitter from a pc with some program?

if you didnt initilize the lock mode, it more likely you have a broken belt or gear that opens the door.

Open unit. Remove disc. Buy new player.

Yes, that is basically it. IrScrutinizer and this hardware. But there are also other possibilities.