Formatted HD by accident! How do I recover?!

Shirasaki

macrumors G3
May 16, 2015
9,964
3,857
If you just delete that partition on external HD and didn't do anything else, you can try to recover partition table, as data is still on your hard disk, and possibly they are still intact.
Assume your "delete an external HD" is "deleted a partition on your external HD".
 

throAU

macrumors 603
Feb 13, 2012
6,440
3,956
Perth, Western Australia
Before doing anything:

1. Do not panic
2. How important is the data to you? If it's work related and losing it will cost you money, don't screw around, get a professional to help you recover it.

The more activity you do to the disk to unsuccessfully recover, the more likely it is you'll prevent being able to get the data back.

There are unformat tools available, but again, if it is important and would cost you money to lose, don't mess about if you don't know what you're doing...
 

Shirasaki

macrumors G3
May 16, 2015
9,964
3,857
Yeah. As throAU says, if data is crucial, bring it to professional data recovery company and start from there.
If data is not crucial, you can try out data recovery software. But you need to extract an exact copy of the entire disk, and recover from there. Don't operate on original disk. If recovering data from replica doesn't work, then ask for professional help.
 
Last edited:

fisherking

macrumors 604
Jul 16, 2010
7,182
2,133
ny somewhere
turn it off, don't do ANYTHING with it. get something like data rescue, and be patient. IF that doesn't work, you need a data recovery company. personally, i think shirasaki has it backwards.

i did this for someone a few years ago, but with a crashed external drive. so, the other important thing; back EVERYTHING up always; our external disks need that just as much as the internal ones. always, at least 2 places for all of your data...
 

throAU

macrumors 603
Feb 13, 2012
6,440
3,956
Perth, Western Australia
the problem is, if you do stuff to the disk that does not work, you are making it less likely for subsequent efforts to be successful.

Don't get me wrong, i'm not saying you can't get it back yourself, just that if it will cost money to lose, and you're not confident, don't just try random stuff hoping you'll eventually get it back via trial and error.

with data recovery, everything you do makes it harder to recover....

If it's just stuff that would be inconvenient but no big disaster to lose, by all means have a go...
 

fisherking

macrumors 604
Jul 16, 2010
7,182
2,133
ny somewhere
Backwards? Could you explain this to me? Thank you so much.
i'm just suggesting he start with data recovery software, and if that doesn't work, to then go to a data recovery company. but...on second thought, this isn't a crashed drive, it's a newly-formatted one...and a recovery company may be the best bet. apologies!
 

Shirasaki

macrumors G3
May 16, 2015
9,964
3,857
i'm just suggesting he start with data recovery software, and if that doesn't work, to then go to a data recovery company. but...on second thought, this isn't a crashed drive, it's a newly-formatted one...and a recovery company may be the best bet. apologies!
Oh, gotcha.
Thanks for explanation. :)
 

Fishrrman

macrumors Core
Feb 20, 2009
19,595
6,815
OP:
Do this:

1. Download DataRescue. The download is free.

2. You will need ANOTHER drive to serve as the "scratch drive" for recovery. You cannot get around this.

3. Launch DR and "aim it" at the problem drive.

4. I can't remember if DR has an option to recover from an unintentional re-initialization. If it DOES have that option, try it first. It -might- work at this point.

5. Otherwise, DR should have a "deep scan" option. Try that. Be aware that it could take quite a few hours to run on a large drive. But give it a chance.

6. DR will do its thing, and when done it will present you with a list of "recoverable" files. HOWEVER -- DR (unregistered) will only let you recover ONE file. The purpose of this is to give you a chance to see if it will work for you BEFORE you pay the registration fee.

7. If DR looks like it can do the job, NOW you pay the registration fee, get a code, enter the code, and let DR begin the recovery process.

8. DR will scavenge the problem drive, reassemble and rebuild what files it finds, and save them to the "scratch drive".

IMPORTANT:
Data recovery like this only works if you just did a "quick reinitialization" of the drive. It WILL NOT WORK if you chose to do a "secure erase".
This is because a quick reinitialization only "wipes clean" the directory of the drive, leaving the data "out on the platters" UNtouched. However, a secure erases actually re-writes ones and zeroes to ALL the sectors of the drive. If you've done this, it takes special equipment and techniques to have a chance at recovering the data -- more than you can afford.
 
you might check out Disk Drill, it allows you to recover your partition if it was removed. As long as you didn't zero out the drive you should be alright, if you still have access to one of the partitions and you are not writing data to the other you can run this and restore files. Just be carefull about those dd if=/dev/null of=/dev/sda commands. :D
 

Shirasaki

macrumors G3
May 16, 2015
9,964
3,857
I am using Disk Drill right now and it appears to be working (although it isn't keeping the file structure...).
Good. Wish best luck.
Some other disk recovery software also provides file structure restore function, although I don't remember which provides this function.
 

\-V-/

Suspended
May 3, 2012
3,155
2,688
I used Disk Drill and it found almost everything but it lost all the file folders. Recovered files but not the folders.
I'm glad you got the files back, at least. There's also DataRescue as well https://www.prosofteng.com/datarescue-mac-data-recovery/ ... but they're a lot more expensive. I believe this kept the file/folder structure last time I used it, but it's been ages ... and they've jacked up their price considerably since I last used it. :confused:
 
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Shirasaki

macrumors G3
May 16, 2015
9,964
3,857
I used Disk Drill and it found almost everything but it lost all the file folders. Recovered files but not the folders.
Hmm. At least you have files. Then, you will need to create all folders you need again. Bit of a good chance for you to re-organize them. ;)

In the meantime, there should be other software available which can not only recover files, but also folder structures. But I don't remember what.
 

Fishrrman

macrumors Core
Feb 20, 2009
19,595
6,815
OP wrote:
"I used Disk Drill and it found almost everything but it lost all the file folders. Recovered files but not the folders."

That's "par for the course" with data recovery.

Remember that "folders" (a graphic representation of sub-directories) are "constructs" of the drive's directory, which you "wiped clean" by re-initializing it.

New directory = all the "old" folders are gone.

That didn't mean that the data itself was gone. This is because the data "exists" out on the sectors of the drive (not "within the directory").

So -- DiskDrill "found" the data, but of course it couldn't recover the folders because they were over-written by the new directory.

Be glad you got your data back!
 
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