TestDisk

TestDisk is powerful free data recovery software that was primarily designed to help recover lost partitions and/or make non-booting disks bootable again when these symptoms are caused by faulty software, certain types of viruses or human error (such as accidentally deleting a Partition Table).
Homepage:	http://www.cgsecurity.org/wiki/TestDisk

Description

TestDisk is powerful free data recovery software that was primarily designed to help recover lost partitions and/or make non-booting disks bootable again when these symptoms are caused by faulty software,  certain types of viruses or human error (such as accidentally deleting a Partition Table).