The disk drive /boot/efi is not ready yet or not present Error

Question

I have installed Ubuntu 12.04 64bit version. I have no problem with it until we tried to take a backup by using Acronis True Image software.

Normally, Ubuntu was seen under BIOS menu under "EFI Boot" option. Then, there was a problem with this software and Ubuntu is lost from the EFI Boot menu. Then, Ubuntu cannot boot.

I have used the Boot-Repair software given in the following link.

I have followed the steps given in recommended solution. I have installed GParted, deleted the FAT32 boot partition and created an unformatted partition with bios_grub flag as recommended by the Boot-Repair software.

After completing the recommended boot repair operation, now the Ubuntu starts but gives an error as described in the title.

The disk drive /boot/efi is not ready yet or not present Error. 
Continue to wait or Press S to skip mounting or M for manual recovery. 

If I press S, I can login Ubuntu and use it without any problem.

Also, I have checked and seen that under BIOS menu, Ubuntu still does not exist under EFI boot options. I have searched for the solution in forums and tried the recommended solutions given in the following link, but they did not work.

Please help to solve this problem, can I disable the EFI boot option from Ubuntu?

Answer 1

Edit your /etc/fstab file and comment out or remove the entry for /boot/efi; that should do away with the error message. You're now booting Ubuntu in BIOS mode, not in EFI mode, so you no longer need the /boot/efi partition. (That partition is the "FAT32 boot partition" you referred to earlier, also known as the EFI System Partition, or ESP.)

That said, my suspicion is that you're booting Windows in EFI mode. If so, you'll probably need to use your firmware's boot manager to select which OS to boot. That might or might not be convenient. If you prefer to use something else (GRUB Legacy, GRUB 2, rEFIt, rEFInd, or whatever), you'll need to get EFI booting working again for Linux. By deleting the ESP and re-creating a fresh one, you also deleted the EFI-mode boot loader for Linux. The fix you followed was the hard way to do it; the easy way was to boot into EFI mode (using the Ubuntu installer, say) and use the efibootmgr program to add the Linux EFI boot loader (probably GRUB 2) back to the NVRAM options. You can still do this, but you'll have to uninstall grub-pc and re-install grub-efi. This will entail jumping through a number of hoops. Alternatively, you could switch to something else, such as GRUB Legacy, ELILO, or the kernel's EFI stub loader (if you're using a 3.3.0 or later kernel). See my Web page on EFI boot loaders for much more information on these options. Overall, if you're happy selecting your OS the way you're doing it now, it's probably easier to stick to that method, at least in the short term.