How to Get Your Deleted Files Back with Disk Drill

We’ve all accidentally deleted an important file — or forgotten to save a file after typing up a whole page worth of changes. The latter problem is fixed with Autosave in most modern Mac apps, and the former is usually fixable if you have a Time Machine backup setup or if the deleted file was in Dropbox (where you can undelete files or roll back changes to them for up to 30 days for free, from their site).

But what if you manage to delete a file that wasn’t backed up? Or — even worse — what if you wipe your whole backup disk without meaning to? You’re going to need a disk recovery tool, one that can undelete files. I just had this happen to my personal backup disk, and after recovering from my initial panic, took Disk Drill for a spin to see how much it could get back. This time, I wasn’t just testing an app for a review: I honestly needed the app to work.

The good news: it worked, most of the way. Here’s the good, the bad, and the ugly of disk recovery, and how to get the most of your data back if you ever find yourself in a similar situation.

When Your Heart Drops Into Your Stomach

Here’s what happened for me. My Mac is a 13″ MacBook Air, with 128Gb of internal storage. That’s not too cramped, but you sure don’t want to store all of your photos and videos internally. So, I’ve got a 500Gb USB3 external hard drive, where our full-sized images and videos get stored, along with installers, ISO files from CD/DVD rips, and a backup of everything in my Dropbox (which is where all my documents, code, and lots of my music and pictures live). I’m not too much of a hoarder, since it all fits there, but it has some rather invaluable stuff like our wedding pictures and videos.

But then, I also have VMware Fusion virtual machines on my external harddrive — yes, the same one I use for backups. There’s not internal space in my Mac to have a copy of Windows 8, Ubuntu, and a second test copy of OS X installed, so I keep them installed in virtual machines stored on the external hard drive. They work surprisingly well from there.

Then, I downloaded a copy of OS X Mavericks beta from my developer account inside the OS X virtual machine, and think I’ll copy the installer to my external hard drive before installing it. I access my Mac (the host machine, remember) over the virtual network, open the external drive (that the virtual machine file is stored on and currently running from), and start copying the file over. I noticed that it only showed one file — the OS X virtual machine — on the external drive, but for some reason assumed it was just a quirk.

It wasn’t. The transfer crashed, I shut down the virtual machine, and then opened my external drive on the MacBook. Low and behold, everything was missing other than the virtual machine and the Mavericks installer — and the virtual machine file was messed up too, enough that it couldn’t reboot.

Moral of the story: don’t access an external hard drive through a virtual machine that’s running from said external hard drive. Whether it’s an OS X or VMware Fusion bug that caused the crash, or somehow I went too deep into digital Inception, I don’t know — but I do know that it wiped my “backup” drive.

Digging Through the Scrambles of Your Data

Look through your disks and figure out what to do

Look through your disks and figure out what to do

And that — or hopefully a less crazy scenario — is what Disk Drill is for. It can repair failing disks and find missing partitions, backup your hard drive to a DMG image, do a quick scan to find files of any type that you just deleted, or in the worst case scenarios, it can dig deep and find almost anything that’s been deleted from your drive if it hasn’t been already overwritten. In a case like mine, you need the deep scan. It’ll take quite some time — around a half hour for me — but will start showing you the files that you can recover almost immediately, organized by file type and extension. It won’t recover your original folders, or even your original file names in most cases, but it will find the actual data, or even the parts of it that are left.

It'll find most files — but not virtual machines

It’ll find most files — but not virtual machines

Disk Drill lets you see all of your files as they’re rediscovered, organized by type and format. You can use Quick Look to preview the files as they’re discovered, even while it’s still scanning for other files, so you can stop the scan as soon as the files you needed were discovered. Or, you can mount everything it finds as a disk and browse through the files in Finder, where you can open or copy them as your would normally. You won’t want to do that forever, but it’s a great way to get your files if you only need to get a few. Otherwise, let the scan run the whole way, then recover everything you have to another disk to prevent your files being recovered from getting overwritten.

You'll still need to hunt a bit for your files

You’ll still need to hunt a bit for your files — and get rid of the corrupted ones.

If you’ve spent hours organizing your files into folders, you’re going to be terribly disheartened to see your files organized simply by file type even after you recover the whole drive. If you have a ton of junk on the drive — as I did thanks to the virtual machines — you’ll find tons of files that you don’t want and likely had no idea were on your drive. I found everything from the file copy animation from Windows XP (saved as a .avi file) to cached images apparently from the Windows 8 news app that were terribly corrupted. Worse still, you’ll only see the first 999 files in the top folder; the next thousand(s) will be organized in to group folders on down. Trying to find my wedding pictures among the mess would seem daunting at best.

It turned out to not be so bad, though. The files I wanted tended to be larger, 2-5Mb photos, so just by simply sorting by size I was able to rediscover my photos, with all the metadata intact except for the file name itself. You’ll still have quite the organizing task ahead of you if you need to recover hundreds of gigs worth of files, but it’s at least approachable.

For me, most documents, pictures, and videos came through fine. 8 of my 13 recovered ISO files were fine as well, though figuring out what’s a Windows 8 and Windows XP installer takes opening the ISO and digging through files. None of the DMG files came through openable, though. Your mileage may vary, of course, but if you’re needing to recover documents, pictures, audio, and videos in normal formats you should be fine, but anything else is hit or miss.


Now, the best case would be that you’d never need to use Disk Drill. I sure hope you won’t have to. But this isn’t the only time I’ve needed to recover files — the other time, a memory card was somehow corrupted, and I used Receive on a PC to get the data back years ago. I’ve also accidentally deleted individual files numerous times, but almost always can get the files back from a backup or Dropbox, so these two times are the only times I’ve needed to use a disk recovery app.

But here’s the thing: I’ve needed to use apps like this, and I do backup my files and sync them online. Odds are, you’ll need something like this too, sometime. So bookmark this article, and when you need to restore files from an apparently empty disk, you’ll know how. Disk Drill Pro is rather pricey at $89, but it’s invaluable if you’ve got to recover a ton of files. Plus, if you just deleted a couple files, or want to use its other protection features like the tool to turn a disk into a DMG image, you can likely get by for free. That’s not too bad.