I have connected a failed hard disk which has a detectable FAT32 filesystem. I Dont know the nature of the damage. What is the easiest way to recover the data from the drive?
There are lots of utilities to recover deleted files, but what if you can’t boot up your computer, or the whole drive has been formatted? We’ll show you some tools that will dig deep and recover the most elusive deleted files, or even whole hard drive partitions.
Testdisk includes TestDisk, which can recover lost partitions and repair boot sectors, and PhotoRec, which can recover many different types of files from tons of different file systems.
Foremost, originally developed by the US Air Force Office of Special Investigations, recovers files based on their headers and other internal structures. Foremost operates on hard drives or drive image files generated by various tools.
Scalpel performs the same functions as foremost, but is focused on enhanced performance and lower memory usage. Scalpel may run better if you have an older machine with less RAM.
Or you can use Redo Backup and Recovery
Redo Backup and Recovery is a GPLv3 Perl script built with a GTK2+ interface designed in Glade. It is simply a front end to partclone, which performs the actual backup and restore. The live CD is built on Ubuntu to provide a graphical user interface and unmodified binaries of each program, but the script will run on any Linux platform that has the required programs installed. The Perl source code for the backup script is contained on the live CD itself.
Redo doesn't need Windows. Download and burn the ISO, place it in your CD-ROM drive, and reboot your machine. The system will load a complete mini operating system with a point-and-click user interface into your computer's memory, without writing any information to your hard drive. Then you will be able to perform backup, restore and recovery actions—guaranteed—even if you aren't able to boot into your regular operating system.
When I searched for the answers of this question, I get EaseUS Partition Recovery freeware that can Recover accidentally deleted NTFS partition, as well as FAT, Ext2/Ext3 file system.
Data Rescue PC3 is a more professional Hard drive data recovery software that is safe to use.
You can get more information from here: Data Rescue PC3