I made a Carbon Copy Cloner clone of a hard disk to an external EVO 850. Then the EVO 850 was placed internally to MBP 2011 and all worked perfectly fine.

Because there was a problem with the MBP 2011, I removed the EVO 850 and placed back the hard disk. It was sent for repair but instead we got another MBP 2011.

The 'new' MBP is working fine with the hard disk so I replaced it with the EVO 850. MBP did not boot normally but seemed to boot from the recovery partition showing a "OS X Utilities" window with 4 options of which one was Disk Utility.

The EVO 850 showed up as "Untitled". First Aid ran fine and ended in Okay quickly.

I swapped the disks again with EVO 850 as external via USB. Shows up the same way in Disk Utilities and MBP is working fine with hard disk.

When running # diskutil list is shows up as

/dev/disk2 (external, physical) 
0: GUID_partition_scheme                               500.1GB
1:                                 EFI EFI             209.7MB
2:                           Apple_HFS                 499.1GB
3:                          Apple_Boot Recovered HD    650.0MB

How do I get this disk to behave as a bootable disk again, or if that's not feasible, how can I access it and save some data?

  • I don't think you are using CCC clone correctly. The disk you clone to is your external disk. If you have an issue with your boot disk, you boot off the external (the clone) and copy everything back to your internal. If you wanted to make a clone of your internal disk to an SSD, you should have used dd instead. – Allan Oct 27 '16 at 14:58
  • @Allan Thanks. But how do I resolve my issue with the CCC'd SSD (which did work inside the other MBP)? – meaning-matters Oct 27 '16 at 15:28
  • What are the sizes of the HDD and SDD respectively? – Allan Oct 27 '16 at 15:36
  • @Allan Both are 500GB, with roughly half used. – meaning-matters Oct 27 '16 at 15:37
  • I am assuming that your data is on the SSD which is cloned that's what you want to get to, correct? Also do you have a USB installer of Sierra or El Cap? I prefer to do a clean install, but you can "reverse" clone the drives. One last thing...holding Option as you turn on your Mac with the SSD connected (external), you should be able to boot off of it. Can you test that out? – Allan Oct 27 '16 at 15:52

This fix is going to involve moving the changed data from the SSD to the HDD so you can then do a clean install on the SSD.

  1. Move data from the SDD to the HDD
  2. Verify data on HDD
  3. Swap HDD and SDD (SDD to be internal)
  4. Wipe SDD and do a clean install of OS
  5. Migrate data from SSD to HDD
  6. Set up CCC to clone SSD to HDD as backup.


You should have the following:

  • USB Installer of macOS Sierra or OS X El Capitan
  • Preferably a different HDD (you only need a 250 to 300GB drive to backup the SSD)
  • A backup of your Keychain
  • A backup of your Application Settings where applicable

1. Move data from the SDD to the HDD

In your comments you said that the data on the SSD changed. You need to copy over the user data from from the SSD to the HDD.

Preferably, you should have another HDD to do a quick clone of your SSD as an extra layer of insurance. However, it's not absolutely necessary.

To move your data from the SSD to the HDD you need to create a directory on your HDD somewhere and call it SSD Data Backup or something that identifies it as where it came from. You can do it in your home directory, it really doesn't matter, just so long you know where it is. Then go into the SSD /Users/ directory and copy over your entire directory to the SSD Data Backup you created earlier.

2. Verify data on HDD

Make sure that everything you copied over from the SSD is on the HDD. I can't stress this step too lightly. Once you proceed there's no going back.

3. Swap HDD and SDD (SDD to be internal).

Now that you have a backup of your SSD data on your HDD, it's time to swap out the drives. You should now have the SSD internally and the HDD externally. Don't connect the HDD until you have finished step 4.

4. Wipe SDD and do a clean install of the OS.

Delete the partitions, everything. You need to have a single partition so that when the OS is installed, it will create all the necessary partitions for you like the boot partition, and the recovery partition. Set it up like you just got it from the factory.

5. Migrate data from SSD to HDD.

Once you have your new OS installed on your new SSD, it's time to move the data back. Attach the HDD (now external) and you can copy things back. You can use:

  • Migration Assistant
  • Copy the whole directory and retake permissions
  • Copy individual items

(I personally go for the third option because it allows me to do a genuinely clean install)

6. Set up CCC to clone SSD to HDD as backup.

Once you have everything setup to your satisfaction, you can now use CCC to clone your SSD to your HDD. Keep in mind the way CCC works is that you clone your drive to an external for backup purposes. If/When things go sideways, you get a new drive and clone FROM the external to the new, not swap.

  • Thanks for the very detailed answer! How do I access the SSD as it does not show up in Finder? – meaning-matters Oct 27 '16 at 17:01
  • Based on the disk partition info in the question, issue the command diskutil mount /dev/disk2s2 and you should see it appear on your desktop. The GUI version of diskutil should allow you to mount it as well. – Allan Oct 27 '16 at 17:07
  • diskutil mount says it can't mount. Adding the readOnly option did not help either. – meaning-matters Oct 27 '16 at 18:34
  • Try it with sudo. What about just mounting the whole disk diskutil mount /dev/disk2? – Allan Oct 27 '16 at 18:37
  • I was already #. diskutil mountDisk /dev/disk2 says One or more volume(s) failed to mount Wait it did appear now in Finder as EFI (result of mounting s1) but that's fairly empty: EFI/APPLE/EXTENSIONS/Firmware.scap only file. – meaning-matters Oct 27 '16 at 18:41

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