Had the same problem and found this solution somewhere on the web
Launch a terminal and run the following commands
$ gconftool-2 --shutdown
$ rm -rf ~/.gconf/apps/panel
$ pkill gnome-panel
It solved the problem for me and got the ubuntu top panel restored, works great!!!

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Worked, thanks :)
- Visitor 16 weeks 1 day agoThat worked for me too. Thanks!
- Visitor 18 weeks 7 hours agosupper its fine that is working thanks a lot
- Visitor 35 weeks 5 days agochandru
worked for me - phew!
- Visitor 1 year 1 week ago