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My internal 250GB failed on me the other day, so I replaced it with a new SSD and HDD combo. I have the failed disk connected via USB/SATA, but it will not mount. However, it shows up under System Profiler.

The following is from System Profiler:


  • Capacity: 250.06 GB (250,059,347,968 bytes)
  • Removable Media: Yes
  • Detachable Drive: Yes
  • BSD Name: disk4
  • Product ID: 0x0731
  • Vendor ID: 0x05e3 (Genesys Logic, Inc.)
  • Version: 90.94
  • Serial Number: 37007
  • Speed: Up to 480 Mb/sec
  • Manufacturer: Genesyslogic
  • Location ID: 0x24130000 / 4
  • Current Available (mA): 500
  • Current Required (mA): 192
  • Partition Map Type: GPT (GUID Partition Table)
  • S.M.A.R.T. status: Not Supported
  • Volumes:
    • disk4s1:
      • Capacity: 209.7 MB (209,715,200 bytes)
      • BSD Name: disk4s1
      • Content: EFI
    • Macintosh HD:
      • Capacity: 184.48 GB (184,484,454,400 bytes)
      • BSD Name: disk4s2
    • Unknown:
    • Unknown:
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Have you tried repairing it with Disk Utility? –  timothymh Mar 26 '12 at 1:18
It will not even show on Disk Utility. –  Logan Mar 26 '12 at 2:37

1 Answer 1

By SSD and HDD combo do you mean something like a Seagate Momentus?

I'm really confused by you saying that the disk failed (how did it fail?) but then you have connected it by USB and you expect it to work?

The report you posted doesn't show a

Content:    Apple_HFS

as you might expect to see under Volumes, so it appears to have been corrupted.

If data on this volume is vital and you don't mind spending money to get it back then unplug it right away and take it to a professional recovery service.

If it would be just "nice to have back" then you could try using the First Aid tab of Disk Utility, and see if it can recover the partition(s).

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Sorry for the confusion, what I meant with a SSD/HDD combo is that I replaced the failed hard drive with an SSD and an HDD where the optical drive was, apologies. When I said the disk failed, I meant that the Mac OS would not boot as the disk itself would not mount. It doesn't seem to be doing anything in Disk Utility or Disk Warrior, so I think I'll just tuck it away and wait until I can get it professionally restored. Thank you! –  Logan Mar 26 '12 at 2:33

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