Recovering Data from a Reformatted Hard Drive
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Recovering Data from a Reformatted Hard Drive


After you reformat a drive, any files previously stored on it will no longer be active. However much like files which have been deleted (see the tip for May 30 2015), the files erased during the reformatting process are just waiting to be overwritten - they are still recoverable for the time being. See Michael Arkfeld, Arkfeld's Best Practices Guide: Information Technology Primer for Legal Professionals (LexisNexis 2015) "Data may still be on a hard drive that has been 'reformatted'. When a hard drive is reformatted, the internal address tables a computer uses to keep track of data are reassigned; however the underlying data is generally unaffected."

One tool that can help you recover files lost on a reformatted drive is TestDisk, which can be downloaded for Windows from this site: http://www.cgsecurity.org/wiki/TestDisk_Download

A free version is available.

1. In this example we see how we start with just six files saved to a 16 GB thumb drive. It's nothing fancy. Just something I bought at a drug store one night.

2. Right click on the drive letter in Windows Explorer and select 'Format'. Windows will send a warnIng that the reformatting of the drive is going to delete any data currently on it.

3. We go ahead and as you can see the data is removed from the external hard drive.

4. After downloading TestDisk and unzipping the files to a folder on your hard drive click on the file named 'photorec_win.exe' . A command prompt window will open. Note the software should not be installed on the same drive that you're trying to recover data from.

5. You select the drive that you want to try to recover data from. Just move down with the arrow keys and press Enter when you have what you want.

6. Next we indicate which partition we want to search, and also have the ability to selection different options, which include the ability to narrow the search to certain file types.

7. TestDisk know prompts us to choose an Operating System type. If you're using Windows you want NTFS. ext3 is for Linux OSes. See the November 14, 2015 tip of the night.

8. Since I'm working with the free version I have no choice but to select the option to search in FAT32 unallocated space only.

9. Next we choose the folders that we want the recovered files to be saved to.

10. Now the process will begin and TestDisk will begin restoring files which were either present when the drive was reformatted, or had been deleted at some earlier point . The latter category will only be those which were never overwritten.

in my test tonight, TestDisk not only recovered the six files which were on the flash drive before reformatting, but also recovered thousands of other files which I had deleted from it months ago. The recovered files are given new file names, but the content is the same and they open without any problem.

Special thanks to Britec09 for his description of this process at,

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