I have an older drive formatted as FAT32, I used to use it for data storage/transfer between Mac OS X and Windows a few years ago. Now I'm trying to recover data from it. It was formatted with two partitions, A and B. Partitions B was corrupted when I was trying to dismount it from OS X, but somehow the dismount progress never finished, it just froze for many hours so I ended up turning off everything. Ever since, partition B never was able to mounted again, while partition A still functions properly. In Disk Utility, I do not see partition B listed, so I'm not able to try repairing it throuh Disk Utility. Disk Utility sees partition A on the hard drive, and describes the remainding storage space to be "free space". I've been reading other threads for suggestion. Does this sound like something I should try TestDisk, to rebuild the partition table? Or should I be trying Disk Warrior to recover the files? Do any of these tools do something irreversible to the disk that I should avoid?