Displaying Hidden Startup Applications

The Startup Applications manager ( Applications > System Settings or type in a terminal gnome-session-properties ) only displays a sub-set of applications to control at startup with the remaining applications being hidden.

The hidden autostart applications are in /etc/xdg/autostart. The *.desktop files all contain a line NoDisplay=true. To make them visible in Startup Applications open a terminal and :
cd /etc/xdg/autostart/
sudo sed --in-place 's/NoDisplay=true/NoDisplay=false/g' *.desktop

You can go back to the previous state by typing this into the terminal :
cd /etc/xdg/autostart/
sudo sed --in-place 's/NoDisplay=false/NoDisplay=true/g' *.desktop

This post contains a description of several startup applications.

Link :
http://askubuntu.com/questions/69810/how-do-i-add-remove-the-hidden-startup-applications