Failed hard drive shows MBR format instead of normal GUID?

Hello

I am on OS X 10.9.5 with an iMac G5.


I have a 3TB hard drive that has an unusual problem.

It is a Western Digital 3TB Red WD30EFRX.


I formatted it with two partitions, both 1.5TB.

One was a bootable backup of a 1TB drive. The backup was done by Carbon Copy Cloner and was tested and verified a few times to make sure it worked.

The other was all of my shared media like video and music.


I used it fine for months and then one day it didn't work.


Before I did any diagnostics on it I tried it in a different enclosure. That didn't help.


Disk Utility can see it but the options to verify the disk are grayed out.


I used disk utility from the terminal and see that the entire drive is listed as 'Fdisk_partition_scheme'.


I think this is the problem as I have never used windows and would not have formatted the hard drive to this format. I have never used bootcamp or parallels or similar programs.


I'm sure that I formatted the drive to 'GUID_partition_scheme' and the fact that I used it without problems on my Mac for a long time should confirm that.


I think that somehow the directory format was corrupted and changed from 'GUID_partition_scheme' to 'Fdisk_partition_scheme' rendering the drive unreadable.


Disk Utility screen shot:

User uploaded file


Disk Utility terminal text:


/dev/disk1
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:     FDisk_partition_scheme                        *3.0 TB     disk1
   1:                       0xEE                         3.0 TB     disk1s1

diskutil info disk1
   Device Identifier:        disk1
   Device Node:              /dev/disk1
   Part of Whole:            disk1
   Device / Media Name:      HGST Media

   Volume Name:              Not applicable (no file system)

   Mounted:                  Not applicable (no file system)

   File System:              None

   Content (IOContent):      FDisk_partition_scheme
   OS Can Be Installed:      No
   Media Type:               Generic
   Protocol:                 USB
   SMART Status:             Not Supported

   Total Size:               3.0 TB (3000592494592 Bytes) (exactly 5860532216 512-Byte-Units)
   Volume Free Space:        Not applicable (no file system)
   Device Block Size:        4096 Bytes

   Read-Only Media:          No
   Read-Only Volume:         Not applicable (no file system)
   Ejectable:                Yes

   Whole:                    Yes
   Internal:                 No
   OS 9 Drivers:             No
   Low Level Format:         Not supported


I did some reading and downloaded gdisk but haven't made any changes with it yet.


gdisk terminal text:


GPT fdisk (gdisk) version 1.0.0

Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: not present

Creating new GPT entries.

Command (? for help):

Of course my ultimate question: Is there a way to reformat my drive to the original GUID format with 1.5TB partitions without losing all the data?


I am hoping that just by changing the directory from MBR back to the original GUID the original partitioning and files and directories will be restored.


Thanks in advance for any help.


Jim

iMac

Posted on Aug 18, 2015 10:51 PM

Reply
2 replies

Sep 9, 2015 12:10 AM in response to Kappy

Just as an update in case people with a similar problem may find this later.


I was able to repair the hard drive using GPT fdisk (gdisk).

I just needed some explanation and hand holding.

First I found the sectors marking the original partitions then I rebuilt the table.

All 2+ TB of my data was intact and salvageable.


For further information try googling "How to fix GUID hard drive corrupted to MBR":


http://apple.stackexchange.com/questions/202018/how-to-fix-guid-hard-drive-corru pted-to-mbr

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Failed hard drive shows MBR format instead of normal GUID?

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