When I try to boot I get this message:

error: unknown filesystem. grub rescue> _

results of:

grub rescue> ls

are as follows:

(hd0) (hd0,msdos5) (hd0,msdos1) (hd1) (fd0)

  • Hey I am having the same problem as you had of grub rescue how did you fixed it? can you explain me. – user2014111 May 22 '14 at 7:33
  • 1
    Honestly, user2014111, I actually had to copy the files off of the HDD, and then I re-installed the whole OS. Sorry I couldn't be of more help... -Chandler – Chandler R. May 22 '14 at 14:43
  • Possible duplicate of Grub rescue - error: unknown filesystem – karel Aug 22 at 16:13

If you don't know your Ubuntu boot partition, check them one by one:

ls (hd0,msdos5)/
ls (hd0,msdos1)/

When you hit the right one, you'll get a line mentioning "lost+found" and so on.

Assuming (hd0,msdos5) is the right partition:

set root=(hd0,msdos5)
set prefix=(hd0,msdos5)/boot/grub
insmod normal

Now you'll be able to boot into Ubuntu. Once you do, reinstall GRUB:

sudo update-grub
sudo grub-install /dev/sda
  • I ran the first two commands with (hd0,1) in place of (hd0,5) as (hd0,msdos1) was the correct partition... they produced no message so I assumed they worked, but when I ran insmod normal... it gave me this message: error: file not found. Then I ran the normal command and it rebooted to the same problem (unknown filesystem) I am running 12.04 LTS Server Version if that changes anything. Thanks again! – Chandler R. Nov 12 '13 at 16:18
  • 1
    Nevermind that. I got it fixed! Thank you so much! – Chandler R. Nov 12 '13 at 16:45
  • Ur wlcm. Plz mark as answered. – Pavel Nov 12 '13 at 18:07
  • Hi Chadler..i am getting file not found error when i type insmod normal. please help me – Ekaveera Apr 4 '14 at 6:22
  • Hey, sorry for the late response, I have not been on StackExchange in months. You, Ekaveera, may already have it fixed, but if not, I can try to help you. However, I had the same error. I believe those instructions are for an outdated version of Ubuntu. Easiest fix is to wipe the OS and then re-install. -Chandler – Chandler R. May 22 '14 at 14:46

If you have a UEFI bios make sure you boot through uefi boot and not legacy. Grub is actually there but the bios doesn't allow it to start


The easiest way i found to fix this error was to put in an old windows 98 disk and in dos you can delete and create partitions and then format

protected by Community Oct 25 '14 at 10:37

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