If you've been using computers for a decent amount of time there is a good chance someone has told you that data stored on a hard drive is not exactly safe. I'm here to assure you that this is indeed true.
Never mind the fact that unlike tapes or CDs or other methods of storage, hard drives are mechanical, active devices and are thus subject to comparatively rapid breakdown.
No, the real threat to hard drives are the people that use them, by which I mean you and me. Hard drives, being the dynamic storage devices that they are, are extremely easy to erase in any number of amusing and simple to achieve ways... as are USB hard drives and flash memory cards (recovery tips for that media is detailed here). Also recently added; How to fix a 1TB hard drive that suddenly changes to 0.0GB, or 32MB in size.
Working as a computer tech during the glory days of Windows XP, you get rather used to using FDISK and other hard drive utilities to prepare and repair customer's drives, which leads to a certain over confidence. That attitude can lead straight to disaster, sort of like giving a 12 year old boy the keys to an ATV.
There are many excellent commercial recovery packages out there. The majority of these are designed to access the disk through an operating system, in which case you will need to have your affected drive transferred to another computer, or at least have a separate drive with a new OS on your original system.
Commercial recovery programs generally use the 'virtual recovery technique, which involves creating an 'image' of the disk to be restored in memory and then transferring files from that image to an alternate hard disk. Two good examples of this type of program are 'Active File Recovery' and R-TT.com's R-Studio.
I did not comprehensively test any of the listed programs, but when I first lost my data, I used several demo and preview versions of the following software to ascertain that my data was actually still there. One standout was R-Studio, whose demo version allows the recovery of files up to 64K in size, allowing me to move my articles safely off the drive before commencing the recovery in earnest. Highly recommended.
From previous work experience, I can also recommend 'Winternals Disk Commander', though they do not provide a preview of the software. Following is a partial list of commercially available partition/file recovery and undeletion software we suggest you check out if the freeware we have already mentioned hasn't done the trick.
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