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This is a question relative to the post How to fix "error: unknown filesystem. grub rescue

I've follow the post of virpara step by step on an Asus EeePC 1015PEM (don't know if it's usefull to presice this, in fact yes, it's to say that I can't insert a CD in this computer...) and i'm stuck on step 5 (Load the Linux kernel and initrd image)

I've typed, in this order :

set prefix=(hd1,msdos1)/usr/lib/grub/i386-pc
insmod linux
//seen that on an other website

loopback loop (hd2,msdos1)/Setup/ubuntu-12.04.1-desktop-i386.iso 
//the image is on an external hard disk (does it matter ?)

set root=(loop)

and had no return message (no error message), then when I typed :

linux /casper/vmlinuz boot=casper iso-scan/filename=/ubuntu-12.04.1-desktop-i386.iso noprompt noeject

here, I have the famous message:

error: unknown filesystem

I don't really know were is my mistake but I suppose it makes impossible for me to reach further steps and achieve grub recuperation.

I'll be grateful if someone could explain were seem to be my problem.

share|improve this question
What is the filename of the image on the external disk? You'll want to set the path on the loopback loop step to that where the disk is. – hexafraction Oct 2 '12 at 23:51
The image is "ubuntu-12.04.1-desktop-i386.iso" it's located in the "Setup" directory (this diretory is in the root of the external drive). I had verify (using combinations of ls commands) the path. I'm not sure to understand your question... the image is on the external (hd2) and on the parttion msdos1 (there is only one partition on this external disk) and the partition where i want to install (reinstall in facts) precise pangolin id (hd1,msdos1) I don't understand what's the problem since I think I've followed correctly the steps. – Teurkidosh Oct 3 '12 at 12:34
What filesystem is the disk? Can GRUB use that filesystem? – hexafraction Oct 3 '12 at 19:12
By filesystem, I suppose you talk about something like FAT* NTFS ext* or something... – Teurkidosh Oct 3 '12 at 22:46
Yes. Which one is it? – hexafraction Oct 3 '12 at 22:53
up vote 0 down vote accepted

I aswer my own question because I think I found an answer by myself...

I've finally bought an external CD/DVD player and boot from this device (with a live CD of Ubuntu inside) and then I could reinstall the whole system.

Note that I initially wanted to erase the old partition, so reinstalling was not a problem for me. Of course, my sollution is not a free one (I've choosen a model ~ 40€...), but it works.

share|improve this answer
Would a Live USB have worked? I assume the computer has USB ports, but I don't know if the BIOS supports booting from USB. – Tom Brossman Oct 7 '12 at 12:04

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