Have a 16" dell flat screen monitior. The display are very dim,and make for hard viewing. Tried to push buttons on computer but a locked icon flashes up. Tried holding the buttons to unlock but did not work. Did have my boys try also without sucess. They are not experts but use computers more. HELP

Laptop shuts down / crashes after closing lid - used to hibernate ...

en.community.dell.com/support-forums/laptop/f/3518/t/19496556

Dell
Mar 13, 2013 - 16 posts - ‎7 authors
Now shuts down after closing the lid after several hours - at least .... My computer crashes when it goes to sleep regardless of the lid's position. E7440 - sleep Issues and display issues - General ...
16 posts
Apr 17, 2014
crash after sleep/close lid - General Hardware - Laptop ...
16 posts
Nov 21, 2012
More results from en.community.dell.com

Laptop Sometimes Crashes When Close Lid to Sleep - Windows

Zaheer khan,
To unlock the monitor controls and get rid of the lock you can press and hold the menu button in for 20 seconds. You can also try the information listed in the link below.
http://www.paulstravelpictures.com/Dell-LCD-Monitor-Flashing-Padlock-Icon/index.htm
Thank You,
Dell-Jesse L
Dell Social Media and Communities

Many monitors have an on-screen display lock (the padlock icon) that seems to get stuck.
Various suggestions in the links below - the one that seems to work most often is to hold the monitor's menu button down for 15-20 seconds to get the screen menu, then either try unlocking the OSD (On Screen Display) or do a factory reset on the monitor.
http://www.fixya.com/support/t448684-flashing_padlock_icon_in_middle_screen
http://www.paulstravelpictures.com/Dell-LCD-Monitor-Flashing-Padlock-Icon/index.htm
Different monitors have slightly different menus, but if it's a Dell monitor you can find the manual below (under Display):
http://support.dell.com/support/systemsinfo/documentation.aspx?c=us&cs=19&l=en&s=dhs&~cat=3

Eve,
To get the lock to go off the screen you can press and hold the monitor Menu button for about 10-15 seconds.
Thank You,
Dell-Jesse L
Dell Social Media and Communites

Hi

It would seem the inverter/LCD light has gone on the monitor

Unfortunatley there isnt much you can do, you can either book in for repair or replacement

Please leave feedback/vote if my answer was helpful

The padlock is an indication that the On Screen Display is locked. You can also lock or unlock the OSD by pushing the Menu button for over 15 seconds.
http://support.dell.com/support/edocs/monitors/e171fp/en/controls.htm

That's the buttonsd on the monitor, not the PC.
Press the [menu] button on th emonitor.
The screen will show the labels of the buttons now.
press the "arrow" to position to the brightness setting (the "sun" icon)
press the minus [-] button to dim
Press [Menu] to save & exit the OSD (on screen Display)

change micro switches..

accoreding to the dell support website, it says to do this
FROM DELL:
NOTE: You can also lock or unlock the OSD by pushing and holding the Menu button for 15 seconds. In this mode All buttons will be locked including the "Menu" button. You can unlock by pushing and holding the Menu button for 15 seconds.

web link: http://support.dell.com/support/edocs/monitors/2005FPW/En/setup.htm

But this fix DID NOT WORK for me....maybe it will for YOU....good luck.

Yep. Sounds like one of the buttons is shorting out and causing the icon to pop up. You can try canned air. If your good with tools, See if you can take the bezal(the plastic part around the screen) apart to clean the button contacts.