I too experienced this bug: my perfectly-functional Ubuntu 13.10 (x86_64) system was rendered unbootable on upgrade to 14.04 with the grub "grub_term_highlight_color" error. My computer has two disk drives: one with Windows 8 and one with Ubuntu. I use GPT/EFI exclusively, with secure boot turned off. My EFI partition was formerly located on the Windows 8 drive.
To fix this problem, I created an empty EFI partition on my Ubuntu disk and installed rEFInd from its installer script. It appears that my motherboard's EFI does not remember NVRAM settings for symbolic names like "ubuntu" or "refind": it only remembers which device (i.e., disk) from which it should boot. In order to make refind work, I had to install it from its install script [1] as
./install.sh --usedefault /dev/sdXX
which makes refind the device default for the disk on which it is installed. Caution: read the install script's manual carefully first! Now I can boot both OSs.
I am not sure if this is the correct solution, but it helped me. If your system has been rendered unbootable in this state, Super Grub Disk can get you back into your OS so you can make these changes.
I too experienced this bug: my perfectly- functional Ubuntu 13.10 (x86_64) system was rendered unbootable on upgrade to 14.04 with the grub "grub_term_ highlight_ color" error. My computer has two disk drives: one with Windows 8 and one with Ubuntu. I use GPT/EFI exclusively, with secure boot turned off. My EFI partition was formerly located on the Windows 8 drive.
To fix this problem, I created an empty EFI partition on my Ubuntu disk and installed rEFInd from its installer script. It appears that my motherboard's EFI does not remember NVRAM settings for symbolic names like "ubuntu" or "refind": it only remembers which device (i.e., disk) from which it should boot. In order to make refind work, I had to install it from its install script [1] as
./install.sh --usedefault /dev/sdXX
which makes refind the device default for the disk on which it is installed. Caution: read the install script's manual carefully first! Now I can boot both OSs.
I am not sure if this is the correct solution, but it helped me. If your system has been rendered unbootable in this state, Super Grub Disk can get you back into your OS so you can make these changes.
[1] http:// www.rodsbooks. com/refind/ installing. html#extra_ installsh