Ubuntu 11.10 install using the Upgrade Now option corrupted tbe Fedora 16 /boot/grub2/grub.cfg file. To recover it, this is what can be done:
- Boot from the DVD or the Net Installation version. Note that the Live CD will not help.
- Select the Troubleshoot menu option and from within that, select the Rescue menu option
- One you get past the selections for the language, and more, you should select to go into the shell.
- At the # prompt, type chroot /mnt/sysimage <enter>
- At the # prompt, type /sbin/grub2-install /dev/sda <enter>
This re-installs the grub.cfg file into the /boot partition. Note that in my case the boot partition was in /dev/sda.
Reboot the system.