Upgrade --> No boot anymore

[Diako]

I received today a microSD to USB adaptater.
I put my sd card in error in the adaptater and i prepared a new sd card with a fresh installed xbian rc3.
I boot on the clean xbian without any problem and i mount the old sd card.
A "ls" command on the old sd card returned this :

Terminal

total 16K
drwxr-xr-x 1 root root 38 Sep 25 13:25 .
drwxr-xr-x 1 root root 10 Feb 7 12:04 ..
drwxr-xr-x 1 root root 2 Feb 7 11:57 data
drwxr-xr-x 1 root root 2 Sep 25 13:25 home
drwxr-xr-x 1 root root 2 Sep 25 13:25 modules
drwxr-xr-x 1 root root 2 Sep 25 13:25 root

Can i do something to save my sd card now i can access to the content of the failing sd card ?

EDIT :
i looked for fstab file and i found "./root/@/etc/fstab" file.
Or the file doesn't contain the permanent usb drive configuration i added.
I don't find any other fstab file on the card...
Have i lost all i did on the sd card ?

EDIT 2 :
I found the good file in this folder : <MOUNT>/root/@last_good_known...