ViewSonic VG2455 User Manual page 29

Key Description
2 + 4 Press and hold the keys to lock/unlock the Power button.
When the menu appears on the screen, continue holding both keys
for 10 seconds to lock/unlock the Power button.
If the Power button is locked, the below message will appear on the
screen:
3 + 5 Press the keys to display/hide the boot up screen when the device is
turned on.
Power Lock/Unlock
Locking Power Button
3
Press and hold for 10s
to lock power
Power Lock/Unlock
Power Button Locked
Boot Up Screen On/Off
Off
Press to turn on
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