Restart loops back to GNU Grub in 11.04

John, try to boot up at grub prompt (when grub menu appears, type 'c')
Enter the following and press 'enter' at each line.

set root=(hd0,x)
linux (hd0,x)/vmlinuz root=/dev/sdax ro
initrd (hd0,x)/initrd.img
boot

Note if your Ubuntu is at say, /dev/sda8 (hd0,8), enter as follows...

set root=(hd0,8)
linux (hd0,8)/vmlinuz root=/dev/sda8 ro
initrd (hd0,8)/initrd.img
boot

If it boots okay, then at terminal,
sudo grub-install /dev/sda (assuming sda)

ps; will send in next message if this doesn't work also
      (so as not to distract you from this)

If the earlier message don't work, boot up live cd, and at terminal,
sudo mount /dev/sdax /mnt
sudo grub-install --root-directory=/mnt /dev/sda

where /dev/sdax (x is a number) of the ubuntu partition
also assuming it is sda and /boot is in /

The earlier message did not work. I originally did an upgrade from 10.10 to 11.04, should I have done a re-installation?
As for your second suggestion, should I burn a live CD?
Thanks

Yes John, burn a livecd.
Good luck.

sudo mount/dev/sda5/mnt
result: command not found
sda - yes
boot in / - yes
I tried this in the terminal in system and then running the live CD and got the same answer
Am I doing something incorrectly?
John

A clean, instead of the upgrade, install solved my problem.
Thanks

Thanks Goh Lip, that solved my question.