Having same issue. Tried running Terminal Fix below with no success..
My main drive is identified as
disk0
To make sure your disk is identified ad “disk0″, fire up the terminal and type in
> diskutil list
If your root drive is marked as “disk0″ then you are all set and ready to being:
First, we have to mount and reformat the EFI partition. For that open a new terminal and type in the commands as is:
> sudo -s
<enter your password>
> newfs_hfs -v EFI /dev/disk0s1
> mkdir /Volumes/EFI
> mount_hfs /dev/disk0s1 /Volumes/EFI
At this point the partition identified by the volume name “EFI” is reformatted and mounted and is ready to be written upon with the boot loader files. We will be using the boot loader which is already installed on the UnibeastUSB.
So, plug in your Unibeast USB drive if it is not already plugged in. Then, open a new terminal window and type in
diskutil list
to identify your EFI partition (it will be under IDENTIFIER). Double check that you are using the correct partition (for me it was disk0s1). Now type the following as is.
> cd /Volumes/UnibeastUSB/usr/standalone/i386
> sudo -s
<enter your password>
> fdisk -f boot0 -u -y /dev/rdisk0
> dd if=boot1h of=/dev/rdisk0s1
> cp boot /Volumes/EFI
Close terminal. Now drag and drop /Extra file from your root drive to the EFI partition. Once copied, make sure to set the new EFI partition as ACTIVE. To do this open a new terminal and type in the following:
> sudo -s
<enter your password>
> fdisk -e /dev/rdisk0
(press) p
(type) f 1
(press) w
(type) y
(type) quit
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