Volume Control (icon) is Gone at Ubuntu 10.04

Question :

• After installing Ubuntu 10.04 (Lucid), my volume control is missing. How can I get it back?

1. Right-click on the panel where you'd like the volume controller to appear and select "Add to panel"
2. Choose "Indicator Applet" from the list and click on "Add" and you're done. The volume control should be back.