How To: Recover Deleted Files On Mac OS X

Have you ever accidentally emptied the trash on your Mac, or intentionally emptied your trash only to realize you’ve made a mistake and need one of those files back? Not to worry – there are a couple of ways that you can go about getting those files back!

Introduction

Before we dig in, there’s some important background information you may want to be aware of. The HFS file system used by Mac OS X is unique in that any file you delete actually still exists until its written over by something else. The file exists within your drive’s free space and can be recovered until another file needs the same space and overwrites it. Additionally, your Mac is smart enough to leave a bit of buffer so that an accidentally deleted file doesn’t get written over immediately.

Still, however, it’s only a matter of time before another file or application will need the space occupied by that deleted file, therefore any time you accidentally delete a file from the trash, your first course of action should be to stop what you are doing as soon as possible in order to prevent it from being written over top of.

There are a couple of methods you can use to recover any file that may have been deleted, and I’ll discuss what I consider to be the two best options that you have when you do make a mistake and delete a file you may have needed.

Time Machine

Your first and most available method to recover your deleted files is Time Machine on your Mac, which also happens to be the best free option available to you. If you keep a Time Machine backup of your Mac and make sure that you always allow Time Machine to back up before shutting off your Mac at day’s end, there is a good chance that the file is stored in your Time Machine backups.

In this case, you can simply enter your Time machine backup by clicking the Time Machine icon in your Mac’s menu bar, and then selecting “Enter Time Machine.” You’ll then be able to browse back through your machine’s history to find the file that you nixed.

There’s always a chance, however, that you either haven’t been keeping Time Machine backups, that you haven’t backed up frequently enough, or that the file was on some external hard drive rather than on your Mac’s main drive. Still, don’t worry – even in these sad scenarios there is something you can do, which brings me to the next method for recovering files.

Prosoft Data Rescue

If your Time Machine backup has failed you, if you don’t have one, or if the file was located on an external hard drive that wasn’t included in your Time machine backup, you may need some extra help in order to recover your file. Fortunately, there are many commercially available programs that will help you recover your lost files.

One of the programs that I am familiar with and find to be one of the best options is Prosoft’s Data Rescue 3 LE, which costs $59.99 and is available from the Mac App Store (Mac App Store Link). Depending on your needs, there’s a separate version of Data Rescue 3 available for $99.95 called simply “Data Rescue 3” (without the LE) that also includes a bootable DVD. Data Rescue 3 is an extremely powerful program, but fortunately it’s also remarkably easy to use. See below for some basic instructions.

There are a few things you’ll need to use Data Rescue 3. Before you begin, keep in mind that you’ll need a separate hard drive or a separate volume on your existing drive for Drive Genius to restore your files to. Due to the nature of how programs like this work, you can’t use the same drive you’re scanning to store the restored files.

Your first step when using Data Rescue 3 is choosing which volume to scan. Note that if you need to scan for missing files on your boot drive, you’ll need to use the standard version of Data Rescue 3, as the Mac App Store version can only scan for files on an external drive. This is due to the Mac App Store not allowing programs sufficient administrator access to recover files on the main drive.

You may also install a second copy of Mac OS X and Data Rescue 3 LE on an external hard drive, and use that to recover files from your Mac’s boot drive.

Once you’ve determined which volume to recover files from, and boot into an appropriate environment in which you can recover those files, simply select the appropriate hard drive, select the volume that needs recovery, and click “next.”

Now that you have chosen the appropriate volume, your second step is to choose a task. In the case of restoring deleted files, you’ll want to choose the “Deleted files scan,” and then click the start button. Now, simply wait for the scan process to complete, which can take several hours.

After the scan has completed, your third step is to find and mark the files and folders you need to have recovered. Marking a folder automatically marks all the files that it contains. One potential concern is that many of these results will not have the same folder structure or file name as the original file, as the files are found using patterns.

You’ll want to take the time to look through the Reconstructed Files results to make sure you’re restoring the appropriate files. It will help if you have an idea of what the size and file type of the deleted content originally was.

Unfortunately, if Data Rescue is unable to find or recover your deleted file, that probably means it has already been written over by newer data and you probably won’t be able to recover it.

With any luck, this information may be able to save you from a few mistakes – hopefully you’ll never need to use it!

J. Glenn Künzler

Glenn is Managing Editor at MacTrast, and has been using a Mac since he bought his first MacBook Pro in 2006. He lives in a small town in Utah, enjoys bacon more than you can possibly imagine, and is severely addicted to pie.