BACKTRACK5 hint Error:unknown filesystem how to do

Yesterday in the WINDOW7 operating system will be a free space into a disk, the result of the start today, found that the boot interface can not enter, resulting in the Windows7 and BACKTRACK5 operating system I can not get in, and finally found a solution in the Linux community

Workaround:

First step: Find out where the Ubuntu partition and grub directory are located.

If you remember the best, forget it doesn't matter, use the following command to test each one.

Grub RESCUE>LS Carriage Return

List all disks and partitions on this machine, such as: hd0, (hd0,1)

, (hd0,4), (hd0,7), (hd0,8), (hd0,9), etc.

Loop through the following command until the contents of the partition are displayed instead of "Unknown filesystem"

Grub Rescue>ls (hd0,0)/grub carriage return

Let's say that when we try to (hd0,8), the content is displayed successfully.

Step Two:

Grub Rescue>set root= (hd0,8) carriage return//bracket the partition that was attempted successfully in the previous step

Grub Rescue>set prefix= (hd0,8)/boot/grub carriage return

Step Three:

Grub Rescue>insmod Normal Carriage return

Fourth Step:

Grub>normal Carriage return

At this point, you should quit the Grub rescue mode and get into the familiar grub mode

Step Fifth: Fix grub

After entering the backtrack system, sudo update-grub carriage return in the command line

Sixth step:

sudo grub-install/dev/sda

Complete, enter reboot reboot, then select the system you enter