IMac – Why is a hard drive not readable anymore after removing it from the Mac

I have a mid 2010 27" iMac. Until this evening it had an SSD (primary drive with OS X Mavericks installation on it) and a HDD as second drive. The HDD is a Western Digital I built into the iMac in 2012 after the Seagate HDD, which came preinstalled, was about to die.

I want to use the HDD in a external drive case. It is the recent Western Digital My Book Studio. For testing I attached the drive controller via my USB 3 cable from Leap Motion with my iMac and was surprised that OS X tells me, the media could not be read. S.M.A.R.T. state is completely OK.

I bought the drive case from ebay (without any drive) and tested the S-ATA controller to work correctly by formatting another HDD I had here with ExFAT and copying some films on it. A Asus Notebook with Windows 8.1 had no problems reading the drive. So I assume it is not the controller which is causing trouble. Or might the controller be configured to encrypt and decrypt and so cannot read the already unencrypted stuff?

Currently I am running Disk Drill scanning in depth for files to recover. It had different partitions (but I do not recall the partition table type):

• HFS+ for Time Machine backups
• HFS+ for ordinary file storage when using OS
• NTFS for file storage (games) for Windows (which was installed through bootcamp on second partition on the SSD)

Currently I am running Disk Drill scanning in depth for files to recover. Disk Drill shows the drive is not formatted (but it is).

Yes, I know, I should have made backups, but one reason I was like "YOLO!" was that I took such precautions for the really important stuff which is stored somewhere else and another that I did not have any capacity left for that.

That is what is written in system.log when I connect the external drive to the Mac:

Oct 15 20:53:38 peter-imac kernel[0]: USBMSC Identifier (non-unique): 574341545241343535313739 0x1058 0x1144 0x1019, 2
Oct 15 20:53:38 peter-imac kernel[0]: IOSATDriver[0xffffff80369a1c00]::IdentifyDevice JMicron probe failed, trying with PassThrough16
Oct 15 20:53:46 peter-imac kernel[0]: IOSATDriver::Send_ATA_IDENTIFY failed 2 2
Oct 15 20:53:46 peter-imac kernel[0]: senseData: VALID_RESPONSE_CODE=112 (7=valid),
Oct 15 20:53:46 peter-imac kernel[0]: :          SEGMENT_NUMBER=0,
Oct 15 20:53:46 peter-imac kernel[0]: :          SENSE_KEY=2 (7 = FILEMARK, 6 = EOM, 5 = ILI, 3-0 = SENSE KEY)
Oct 15 20:53:46 peter-imac kernel[0]: :          INFORMATION_1,_2,_3,_4=0,0,0,0,
Oct 15 20:53:46 peter-imac kernel[0]: :          ADDITIONAL_SENSE_LENGTH=10,
Oct 15 20:53:46 peter-imac kernel[0]: :          COMMAND_SPECIFIC_INFORMATION_1,_2,_3,_4=0,0,0,0,
Oct 15 20:53:46 peter-imac kernel[0]: :          ADDITIONAL_SENSE_CODE=4,
Oct 15 20:53:46 peter-imac kernel[0]: :          ADDITIONAL_SENSE_CODE_QUALIFIER=1,
Oct 15 20:53:46 peter-imac kernel[0]: :          FIELD_REPLACEABLE_UNIT_CODE=0,
Oct 15 20:53:46 peter-imac kernel[0]: :          SKSV_SENSE_KEY_SPECIFIC_MSB=0 (7 = Sense Key Specific Valid bit, 6-0 Sense Key Specific MSB),
Oct 15 20:53:46 peter-imac kernel[0]: :          SENSE_KEY_SPECIFIC_MID=0,
Oct 15 20:53:46 peter-imac kernel[0]: :          SENSE_KEY_SPECIFIC_LSB=0
Oct 15 20:53:46 peter-imac kernel[0]: IOSATDriver[0xffffff80369a1c00]::IdentifyDevice SAT PassThrough16 failed, retrying with PassThrough12
Oct 15 20:53:47 peter-imac kernel[0]: SATSMARTDriver v0.9: enclosure 'Unknown 1058:1144', disk serial 'WD-WCATRA455179', revision '05.01D05', model 'WDC WD1002FAEX-00Z3A0'
Oct 15 20:53:47 peter-imac kernel[0]: User client already open
Oct 15 20:53:47 peter-imac kernel[0]: Open failed
Oct 15 20:53:47 peter-imac.fritz.box Disk Drill[405]: /dev/disk0
Oct 15 20:53:47 peter-imac.fritz.box Disk Drill[405]: /dev/disk1
Oct 15 20:53:47 peter-imac.fritz.box Disk Drill[405]: -99418112
Oct 15 20:53:47 peter-imac.fritz.box UserNotificationCenter[477]: ApplePersistence=NO
Oct 15 20:53:48 peter-imac.fritz.box com.apple.kextd[14]: Can't create kext cache under / - owner not root.
Oct 15 20:53:49 --- last message repeated 3 times ---
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: found disk: WD WDC WD1002FAEX-00Z3A0 Media, with size: 1000170586112, bsdname: disk2
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: S.M.A.R.T. data (id,curr,threshold,raw) model: WDC WD1002FAEX-00Z3A0, firmware: 05.01D05
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 199   200 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 197   200 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 11    100 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 9 92  0   5937
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 7 100 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 5 200 140 0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 3 195 21  3250
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 1 200 51  0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 193   199 0   3085
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 200   200 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 198   200 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 12    98  0   2307
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 194   111 0   36
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 10    100 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 192   198 0   2034
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 4 95  0   5116
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: 196   200 0   0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: Error determining system volume, trying file systems
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: Error opening file system in partition at offset 0
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: Using it as RAW
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: detect OEM volumes
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: Found filesystem raw, offset 0, size 1000170586112 
Oct 15 20:53:49 peter-imac.fritz.box Disk Drill[405]: Volume: /dev/disk2 (WD WDC WD1002FAEX-00Z3A0 Media) mounted: not mounted

Ignore the Can't create kext cache stuff, that is independent and written all the time.