From our previous slide, we are in the live CD environment. To fix the partition table and get our data back, we need to restore our partition table from the external drive with the following command

dd if=/media/usbdisk/patition_table.bak of=/dev/hda bs=512 count=1

Now we reboot the machine and we should see that our boot loader and our partitions with all of their data are back in order.