Recover Data From Unformatted External HDD

Sep 8, 2018
I have a LaCie 2TB Rugged Thunderbolt Mobile HDD with a 1.8 TB partition and a 200GB partition that I had used for photos on an 11 year old Mac (around 300-400GB of data on it). I bought OneDrive to put the data on the cloud but the computer was so old that the webpage crashed when I tried to upload the files. I have a windows 10 PC that I knew could upload the data so I tried doing it form there. I then realised the partition ID was for Mac OS so I changed it to windows and made it my (G: ) drive. I then realized I had to format it. But since formatting it removed all the data on it and I don't want that. I tried going back on the Mac to back up the files but it needed to be formatted there as well. I am now stuck and I am wondering how to recover the files, back them up somewhere, format it, restore the data on it, and then upload it to the cloud on my windows device.

External HDD Link:

Screenshot of Disk Management:
Formatting a drive overwrites the data telling the drive where the files are located, or potentially even the files themselves, if it were a long format. You should not format a drive that you want to access files from.

If it was a quick format that only removed the data pointing to where files are located on the drive, then it might be possible to recover those files, or the whole partition itself, using a data recovery utility, as was already mentioned. I'm not sure which software would be best for recovering files from a partition that had been accessible from a Mac, but not from Windows though. It may not matter though, if a utility is searching for files at a low-level. Here's an article that lists a number of free data recovery utilities that might potentially help, in any case...

Keep in mind that a scan for missing files using one of these utilities can be quite slow, potentially taking many hours depending on how they look for files. One thing you should make sure to do though, is to not store anything on the drive until you have recovered everything that you wanted from it (or attempted to do so, at least). If the files happen to still be there, but the drive is missing the map pointing to where they are, new files can potentially overwrite them.

I do notice that the drive's product writeup mentions it featuring "AES 256-bit software encryption", but did you make use of such software? If the drive required a password to access files, or otherwise used some form of encryption on the files, recovery might not be possible.
Sep 8, 2018

I tried using the wizard and it said I needed to format it first.
Should I format it and then use the recurva wizard to recover it or am I not doing something right?


Mar 10, 2017
If the data is very important, consider one or both possibilities:
-- find and use a local data recovery person's expertise and pay some monies
-- send the HDD to a data recovery company / specialist and pay monies
I'm guessing you have no backups, so, unfortunately, your options are few. Reading here and other forums indicate that most DIY attempts end up failing in spite of much hard work by HDD owners.
I would try not to use anything that said it needs to format the drive, since in the process of doing so, you may be writing more data to the drive that can potentially overwrite files. There are free recovery utilities that can operate on unformatted drives. I believe one of the better sets of tools for recovering data from unformatted drives is PhotoRec/TestDisk, although they use a command-line interface, which may make them a bit more complex to use. They are available for just about any operating system though.

PhotoRec is designed for recovering photos and other specific types of files from disks, and ignores the filesystem, instead scanning directly for specific signatures that identify sections of data as images or other things, allowing those files to be copied to another drive.

TeskDisk (from the same site) instead can try to repair the filesystem to make the drive's contents accessible again, rather than scanning for individual files.

I'm not super-familiar with exactly what you would need to do in your case though, so you might want to ask elsewhere. That site has an official forum, so it might be worth asking there...



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