|TestDisk is a nice tool that can fix such problem especially on not formatted problem.|
Cons: it is command line built program with poor GUI.
You should take a look at this freeware. If you want to restore files, you can try freeware like Recuva, PCinspector or EaseUS.
You can google to find download link. Or check out a freeware roundup http://www.free-recovery.net