Once the Terminal window opens, enter the following command at the prompt:
gconftool-2 --shutdown
(Note: There should be no spaces between the two dashes before shutdown.)
EDIT – Reader nickrud has suggested a better method instead of shutting down gconfd. Instead use the following command (thanks nickrud!)
gconftool-2 --recursive-unset /apps/panel
(Remember: There should be no spaces between the two dashes before shutdown.)
Then enter the next command:
rm -rf ~/.gconf/apps/panel
And enter one more command:
pkill gnome-panel
