Samsung 2043SN - Manual (Page 44)

When pressing the MENU button after locking the OSD
This is the function that locks the OSD in order to keep the current states of settings or prevent
others from adjusting the current settings.
Lock : Hold down the MENU button for more than five (5) seconds to activate the OSD ad-
justment lock function.
Unlock : Hold down the MENU button for more than five (5) seconds to deactivate the OSD
adjustment lock function.
Adjusting the Monitor