root@ubuntu:/# sudo grub-install /dev/sda 
sudo: unable to resolve host ubuntu
Searching for GRUB installation directory ... found: /boot/grub
Installing GRUB to /dev/sda as (hd0)...

       [ Minimal BASH-like line editing is supported.   For
         the   first   word,  TAB  lists  possible  command
         completions.  Anywhere else TAB lists the possible
         completions of a device/filename. ]
grub> root (hd0,4)
grub> setup  --stage2=/boot/grub/stage2 --prefix=/grub (hd0)
 Checking if "/grub/stage1" exists... yes
 Checking if "/grub/stage2" exists... yes
 Checking if "/grub/e2fs_stage1_5" exists... yes
 Running "embed /grub/e2fs_stage1_5 (hd0)"...  21 sectors are embedded.
succeeded
 Running "install --stage2=/boot/grub/stage2 /grub/stage1 (hd0) (hd0)1+21 p (hd0,4)/grub/stage2 /grub/menu.lst"... failed

Error 6: Mismatched or corrupt version of stage1/stage2
grub> quit
root@ubuntu:/#