I followed the instructions provided in the link Enabling native shortcuts on Gnome - 3 for setting the shortcut of Ctrl+Alt+D for showing desktop and yet it does not seem to work.
I can send a screen-shot of the setting in my system as a new user I am not allowed to attach the image in this query.I have tried logging out as well as restart of my system. Request someone to help on this.


Hide all normal windows. If it is Disabled click on it and press <kbd>Ctrl</kbd>+<kbd>Alt</kbd><kbd>D</kbd>. It works? – Lucio Sep 5 '12 at 18:59