note:The button may be different and the procedure might vary on some monitors. Please check your monitor User Guide to find the exact procedure if this procedure does not work.
HP Customer Support
HP LCD and LED Monitors - OSD Lockout Message Appears on the Screen
This document pertains to LCD and LED monitors.
One of the following messages appears on the screen (over the items being displayed).
... or similar message.
This message occurs when the Menu button on the front panel is pressed for more than 10 seconds. OSD lockout prevents the OSD menu from opening on the screen when a button is accidentally pressed.
To remove the OSD Lockout message, release the Menu button (if something was pressing against it), and press and hold the Menu button again for about 10 seconds - until the message goes away. If the OSD Lockout message does not go away, the button may be stuck or the hardware behind the button might have become defective.
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