There are two places where we store file system information: the MBR partition Table and Volumes boot sector, When the file system information provided on these 2 sectors of disk is not good you may see chkdsk reporting raw file system (though the data is still there).
Ok try this one mount the drive as a slave inside the computer and see if you can repair the partition table:
Download the Windows version of TestDisk.
http://www.cgsecurity.org/wiki/TestDisk
Unzip the downloaded file to your C: drive and open C:\testdisk-6.8\win > double click " testdisk_win" (the program doesn't have to installed).
A. At the first window select “No Log” and press the <Enter> key.
B. Select what drive to analyse, choose “Proceed” and <Enter>.
C. Select partition type – Intel if it’s a PC.
D. Select “Analyse” then <Enter>. The drive/partition will be analysed.
E. Select “Proceed” at the next screen, then <Enter>.
F. Press “Y” if the partitions were created under Vista – “N” if not.
G. TestDisk should say “Structure OK”. Choose the drive/partition to fix. Then press <Enter>.
H. Select “Write” and press <Enter>.
I. Press “Y”.
J. Press <Enter> and close TestDisk. Reboot the computer.