ubuntu-gnome@ubuntu-gnome:~$ sudo fdisk -lu

Disk /dev/sda: 750.2 GB, 750156374016 bytes
255 heads, 63 sectors/track, 91201 cylinders, total 1465149168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x5be4a3f9

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1            2048    52430847    26214400   1c  Hidden W95 FAT32 (LBA)
/dev/sda2        52430848   681576447   314572800    7  HPFS/NTFS/exFAT
/dev/sda3       681578494  1404233727   361327617    5  Extended
Partition 3 does not start on physical sector boundary.
/dev/sda5       681578496  1267513343   292967424   83  Linux
/dev/sda6      1365172224  1384703473     9765625   82  Linux swap / Solaris
/dev/sda7      1267515392  1365170175    48827392   83  Linux
/dev/sda8   *  1384704000  1404233727     9764864   83  Linux

Partition table entries are not in disk order

Disk /dev/sdb: 4009 MB, 4009754624 bytes
128 heads, 22 sectors/track, 2781 cylinders, total 7831552 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xc3072e18

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1   *          63     7831551     3915744+   b  W95 FAT32
ubuntu-gnome@ubuntu-gnome:~$ sudo grub-install /dev/sda7
Path `/boot/grub' is not readable by GRUB on boot. Installation is impossible. Aborting.
ubuntu-gnome@ubuntu-gnome:~$ sudo update-grub
/usr/sbin/grub-probe: error: failed to get canonical path of /cow.
ubuntu-gnome@ubuntu-gnome:~$ sudo grub-install /dev/sda8
Path `/boot/grub' is not readable by GRUB on boot. Installation is impossible. Aborting.
ubuntu-gnome@ubuntu-gnome:~$ sudo mount /dev/sda8 /mnt
ubuntu-gnome@ubuntu-gnome:~$ sudo mount /dev/sda8 /mnt/boot/efi
mount: mount point /mnt/boot/efi does not exist
ubuntu-gnome@ubuntu-gnome:~$ sudo unmount /dev/sda8
sudo: unmount: command not found
ubuntu-gnome@ubuntu-gnome:~$ sudo mount /dev/sda7 /mnt
ubuntu-gnome@ubuntu-gnome:~$ sudo mount /dev/sda8 /mnt/boot/efi
ubuntu-gnome@ubuntu-gnome:~$ sudo mount -o bind /dev /mnt/dev
ubuntu-gnome@ubuntu-gnome:~$ sudo mount -o bind /sys /mnt/sys
ubuntu-gnome@ubuntu-gnome:~$ sudo mount -t proc /proc /mnt/proc
ubuntu-gnome@ubuntu-gnome:~$ sudo cp /proc/mounts /mnt/etc/mtab
ubuntu-gnome@ubuntu-gnome:~$ sudo chroot /mnt /bin/bash
root@ubuntu-gnome:/# grub-install /dev/sda8
Extended partition info not supported.
Error: no partition information on disk /dev/sda.
       Cowardly refusing to create a boot option.
Installation finished. No error reported.
root@ubuntu-gnome:/#