So I have a WD 1TB laptop hard drive in an external enclosure, it was put into an xbox360 and formatted to "ExFAT" (320GB partition) after I tried to reformat the drive into "NTFS" I can format the 320GB into "NTFS" but the other 700GB are missing. I have ran Chkdisk on the hard drive and it came up with no errors. I have opened it up in disk management and you can only see the one partition that is 320GB (please see picture in link). I have even ran WD's "Data Lifeguard Diagnostic" with 0 success. Does anyone have any ideas on how I can recover the missing 700GB to restore the hard drive to its original condition.
*note: There is no data on the hard drive at all