It sounds like the drive may be corrupt. TestDisk http://www.cgsecurity.org/wiki/TestDisk sometimes fixes corrupt drives. EaseUS has this http://www.easeus.com/datarecoverywizard/free-data-recovery-software.htm and Recuva is free http://www.piriform.com/recuva I don’t know how many of these work on Windows 8. These have helped people recover data in the past. Also look in Windows Disk Management and see if the drive shows as Raw or anything else abnormal. If it is Raw there might be a last ditch thing to try.
Joe
