File Recovery from an Unbootable Mac Computer

Even a Mac user sometimes can find that his or her computer doesn't start anymore. Its hardware seems to be functioning, but the computer isn't operable anymore. Quite often that may happen after an unsuccessful system update or system crash.

The Mac system provides a system recovery option, but such operation may permanently destroy user's files, such as family photos, music collections, important documents, as so on. So, it's a quite reasonable step to recover such files before recovering the system. Such procedure is called an "emergency recovery" and can be performed using special recovery tools like R-Studio Emergency.

This article will give you step-by-step instructions on how to perform such emergency recovery and save your endangered files. In addition, you may use R-Studio's on-line help if you need some more information.

Also you don't have to buy R-Studio immediately to start recovering files. You may do most actions in its Demo mode except saving recovered files. When you have enough reasons to believe that you will be able to recover files successfully, you my buy R-Studio and register it without interrupting the file recovery process.

Preliminary Steps
Before we begin we need to do some preliminary steps:

First, we need to find place to store recovered files. You may use the following devices:

  • External devices such as USB sticks, memory cards, and other similar FAT-formatted devices. Such devices are inexpensive and easily available, they can be read by all operating systems, but they have one important drawback: they cannot store files larger that 2GB. So, if you plan to recover large video files, this is not your option.
  • External hard drives formatted by Mac computers (with the HFS/HFS+ file system). R-Studio Emergency can write files to such disks, although some files and folders on those disks may have access problems on Mac computers.

    Windows computers cannot read such disks without some third-party software installed. Linux computers are able to access files on such disks, but some access right problems may appear.
  • External hard drives formatted by Windows computers (with the NTFS file system). Mac computers can only read such disks without any third-party software, and Linux computers have full access to such disks.
  • Network disks. Such disks may be on other network computers or NAS devices. Below we'll explain how to connect such disks to R-Studio Emergency.

Then we need to create an R-Studio Emergency startup disk.

Using a Mac Computer
Download the ZIP archive of R-Studio Emergency, unzip it, and write files to a FAT32-formatted USB device.
Please note that you cannot use this disk to start non-EFI computers (old Macs, for example), nor can you just copy those files to a CD/DVD disc to create an R-Studio Emergency startup disc. If you need a CD disk, burn it using the ISO image.

Using a Windows Computer
You may create a USB startup disk for R-Studio Emergency using a Windows Computer. See R-Studio on-line Help: Creating Startup Disks for details. That disk can be used to start any computer.

Now we can start the file recovery procedure:

Starting a Mac computer with R-Studio Emergency
1. Connect a USB disk.

2. Switch the Mac on

3. While loading, keep the Option key on the Mac keyboard pressed (the Alt key if you use a non-Apple keyboard).
The Options key
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4. Select the EFI boot disk and press Enter.
The R-Studio Emergency startup disk
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R-Studio Emergency will start loading.

5. Select R-Studio Emergency GUI (Graphic Mode)
The Startup Options screen
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Wait until the R-Studio Emergency Demo Activation dialog box appears.
Activation screen
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You don't have to enter the activation code immediately; you may click the Cancel button and work with R-Studio Emergency in its Demo mode. In this mode, you may perform all file recovery actions except saving recovered files.

The Main panel of R-Studio will appear.
R-Studio's Main panel
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File Recovery
If R-Studio has recognized a file system on the partition, just double-click it to enumerate the files. When the file/folder structure appears, navigate to the Users folder, and mark folders and files for recovery.
Files marked for recovery
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Searching for and marking files for recovery
You may do that in several ways:

  • Sorting files by their types (extensions):
    Click the Extensions tab on the Sorted by: bar.
    Files sorted by their types (extensions)
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  • Sorting files by their times (Creation/Modification/Access):
    Click the necessary tab on the Sorted by: bar.
    Files sorted by their creation time
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    You may see paths to the individual files on the Contents pane if you select Path on the View -> Contents -> View Columns menu.
  • Finding specific files
    Also, you can find and mark specific files to recover by using the Find/Mark dialog box. Click the Find/Mark button and specify the file(s), their options, and what to do with them
    Find dialog box
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    See the R-Studio on-line Help: Searching for a File for more information on Find/Mark options.

You may estimate the chances of recovering files by using the built-in graphic previewer. Just double-click a selected file, be it a deleted or existing one. The previewer supports most graphic formats.
File previewer
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If you've found all the files that you want and are satisfied with their preview results, you may activate your R-Studio Emergency if it's running in the Demo mode. That will not affect any obtained information; you may continue file recovery right after entering the Activation Code.

Once you've selected all files to recover, click the Recover Marked button. The Recover dialog box will appear:
Recovery dialog box
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See the R-Studio on-line Help: Recover options for more details.

Specify the recovery options and output folder to store recovered files.
Output folder for recovered files
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When all file recovery settings are specified, click the OK button. R-Studio will start file recovery showing its progress.
File Recovery Progress
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The Log panel will show results of file recovery.
File recovery results
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Scanning the disk
If R-Studio cannot find the partition with the files you want to recover, you need to scan the disk. Disk scan is also required to recover deleted files because when Mac OS deletes files it deletes all information about it.

When the scan is finished, R-Studio will show you one or several recognized partitions so you can choose the right one and recover files from it as it's been described in the File recovery from an existing partition section.

To scan the partition, right-click the partition to be scanned and specify the required scan parameters on the Scan dialog box.
Scan dialog box
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See the R-Studio on-line Help: Disk Scan for more details.

Scanning for Known File Types
This is a very useful feature for file recovery from deleted or reformatted partitions. While scanning, R-Studio can recognize to which particular file type the data belong. Using that information, R-Studio can find more files to recover. Those found files appear in the Extra Found Files folder in the scan result.
Known File Types dialog box
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By default, R-Studio tries to recognize the default list of supported file types, increasing time required for the scan. You may reduce it by selecting only those file types that you need. Click the Known File Types... button and select the required file types on the File Types dialog box. These selections will be applied to that scan session only.

You may create your own known file types if necessary. Read the Creating a Custom Known File Type for R-Studio for more details.

When you're ready with the scan parameters, click the Scan button. R-Studio will start scanning. When it finishes the scan, it will show the recognized partitions it's found on the disk.
Scan results
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R-Studio shows them in different colors depending on which elements of the partition have been found.

pdisk.png This represents an existing logical disk or partition.
pgreen.png Both boot records and file entries are found for this partition.
pellow.png Only file entries are found for this partition.
pred.png Only boot records are found for this partition.
pempspace.png This represents the empty space on the object.

To successfully recover files from a recognized partition, it is necessary to find one that corresponds correctly to the real logical disk on which the files resided. No strict rules can be applied to that, but the following tips should be taken into account:

  • If you are going to recover files from a disk with a damaged file system, most likely the right recognized partition will be one coded in green.
  • If you are going to recover files from a previously deleted or reformatted partition, most likely the right recognized partition will be one coded in yellow.

Also, always check the recognized partition's file system, start point, and size. These characteristics should be the same for both the recognized partition and real logical disk/partition. When in doubt, try to preview a couple of files from the recognized partition. If the files are seen correctly, this is the right partition.

In our example, we have only one Recognized0, so the choice is easy. Just double-click the partition and recover the files as we did that for the existing partition.

Computer Shutdown
When you finish file recovery, remove the USB disk, and turn your computer off manually.

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