Cannot find core.img on a 3Tb GPT usb disk

[lukshuntim]

Hi,

I want to install grub2 onto a 3Tb GPT usb disk in linux mint 14 (which 
is based on ubuntu quantal) and have created the BIOS boot partition 
before installing grub2. Here's the partition layout as seen by parted.

Disk /dev/sdc: 3001GB
Sector size (logical/physical): 4096B/4096B
Partition Table: gpt

Number  Start   End     Size    File system  Name      Flags
 2      1049kB  2097kB  1049kB               BIOSBOOT  bios_grub
 1      210MB   2990GB  2990GB               BKUP

Grub2 was then installed onto /dev/sdc (after mounting /dev/sdc1 on 
/mnt/bkup) with

grub-install --target=i386-pc --recheck --boot-directory=/mnt/bkup/boot 
--debug /dev/sdc

grub-mkconfig -o /mnt/bkup/boot/grub/grub.conf

All grub2 files were indeed created but during booting from the usb 
disk, it dropped to a grub rescue shell saying "file not found". Running 
the bootinfoscript (from 
http://sourceforge.net/projects/bootinfoscript/) showed this message

"Grub2 (v1.99) is installed in the MBR of /dev/sdc and looks at sector 
2048 of the same hard drive for core.img, but core.img can not be found 
at this location."

Any help will be much appreciated.

Regards,
ST
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