"To unlock the monitor controls and get rid of the Lock, press and hold the monitor Menu button for about 10-15 seconds.
Buttons =
1 Preset Modes
2 Brightness/Contrast
3 Menu
4 Exit
5 Power
* Power off the PC
* Power off the monitor
* Disconnect the power cord from the monitor
* Disconnect all monitor cords from the PC (USB, DVI, VGA, DisplayPort, HDMI, etc.)
* While disconnected, press and hold the monitor power button down for 5 seconds
* Reconnect the DVI cord to the monitor and to the PC video card
* Reconnect the power cord to the monitor
* Power on the monitor if it does not power on by itself
* Power on the PC
* Press the monitor Input Source Select button and choose DVI"
probaj.