Just Updated my Ubuntu System to new kernel and also other security updates.
But after the update was applied and I restarted my system, all the gnome-panel icons were missing and the right hand corner of the panel where I have System Date, Network Icon, indicator-applet, all were missing.
So just in case you face the same problem here are some solutions which I have used.
Note: type the commands on terminal. 🙂
You can refresh the panel with:
killall gnome-panel &
If you want to return the panel to the default settings:
gconftool-2 –recursive-unset /apps/panel && killall gnome-panel &