Accidentally removed default gnome panel applications

I accidentally removed the default Gnome panel menu on the top right (containing clock, mail, volume and shutdown options). After, I tried to get the menu back by adding some apps but that did not solve the problem. I then stumbled upon a reset via the terminal, however, the menu remains missing and the apps I added are still there.

sudo dconf reset -f /org/gnome/gnome-panel/
killall gnome-panel

and

gconftool-2 --recursive-unset /apps/panel
pkill gnome-panel

System: Ubuntu 12.04 with Gnome classic.

Any help is greatly appreciated! Many thanks in advance.

Hold Alt + Right-click an empty area of your panel (in Gnome 3), and choose “Add to Panel…“, then scroll down till you find “Menu Bar”, then drag and drop it on desired place or click Add.

I did this recently as well. Hold Super+Alt+Right Click to add to panel then search for 'Indicator applet complete'. Add that to the panel and everything should be back to normal. The Super is typically the one with the Windows logo on it on most PCs (see What are the meta, super, and hyper keys?).