When I try to add the volume control to my panel, the following question pops up:

The "Volume Control" applet appears to have died unexpectedly.

Do you want to reload this applet?

(If you choose not to reload it at this time you can always add it by right clicking on the panel and clicking on the "Add to Panel" submenu) SELECT NO or YES.

I select YES, and the following question pops up:
The panel encountered a problem while loading "OAFIID:GNOME_MixerApplet".
Details: Unknown CORBA exception id: 'IDL:omg.org/CORBA/COMM_FAILURE:1.0'

Do you want to delete the applet from your configuration? Don't Delete or Delete

I selected Delete. So what can I do from here to resolve this?