This is going to be a long story, but please bear with me...
I'm trying to recover a MacOS X partition that got lost on my Seagate HD. This HD was dual booted using BootCamp with Windows 10. I originally had Linux on this HD too, but eventually deleted it and used BootCamp to put on a Windows 10 install. (This is all on a late 2011 MacBook Pro). I was actually trying to migrate everything over to a solid state drive by using SuperDuper! and Winclone, but something went wrong in the whole process, and all of a sudden I couldn't boot into the MacOS operating system any longer (gave the prohibitory sign). To make things worse, the system couldn't actually find the MacOS partition either.
So I used Apple's internet recovery to at least get a bootable MacOS X going and put the SSD into the MacBook Pro. I then put the Seagate HD into a Sabrent external USB adaptor so I could see what was going on. After booting into MacOS and running terminal, I see this:
/dev/disk0 (internal, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *500.1 GB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_HFS Macintosh SSD 499.2 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
/dev/disk1 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *500.1 GB disk1
1: EFI EFI 209.7 MB disk1s1
2: Apple_CoreStorage Macintosh HD 336.8 GB disk1s2
3: Apple_Boot Recovery HD 650.0 MB disk1s3
4: Microsoft Basic Data BOOTCAMP 110.0 GB disk1s4
/dev/disk2 (external, virtual):
#: TYPE NAME SIZE IDENTIFIER
0: Apple_HFS +336.5 GB disk2
Logical Volume on disk1s2
0F8A5999-AA3A-42E3-AB53-260295D99FA1
Unencrypted
So you can see that it knows the MacOS partition is there (disk1s2), but it won't mount, DiskUtility has no idea what is on the disk (it's greyed out), and I obviously can't browse into it to get any files. I don't know why it lists an external virtual volume as well...this seems to be the MacOS partition as well - i.e. it looks like disk2 is the same as disk1s2. I ran First Aid on it through DiskUtility, but got:
File system check exit code is 8.
Restoring the original state found as unmounted.
File system verify or repair failed.
If you try and run DiskUtility through Recovery on the entire drive, it says something's wrong and that it may be corrupt.
Using the command fdisk /dev/disk1 gives:
Disk: /dev/disk1 geometry: 60801/255/63 [976773168 sectors]
Signature: 0xAA55
Starting Ending
#: id cyl hd sec - cyl hd sec [ start - size]
------------------------------------------------------------------------
1: EE 1023 254 63 - 1023 254 63 [ 1 - 409639] <Unknown ID>
2: AC 1023 254 63 - 1023 254 63 [ 409640 - 657891312] <Unknown ID>
3: AB 1023 254 63 - 1023 254 63 [ 658300952 - 1269536] Darwin Boot
*4: 0C 1023 254 63 - 1023 254 63 [ 659570688 - 214843392] Win95 FAT32L
Using the command gpt -r show disk1 gives:
gpt show: disk1: Suspicious MBR at sector 0
start size index contents
0 1 MBR
1 1 Pri GPT header
2 32 Pri GPT table
34 6
40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
409640 657891312 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC
658300952 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
659570488 200
659570688 214843392 4 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
874414080 102359055
976773135 32 Sec GPT table
976773167 1 Sec GPT header
I think this might be similar to an issue someone was having here:
Prohibitory sign on boot after Sierra update, can't mount disk anymore
but I'm not sure, so I thought I'd post this.
Any help that anyone can provide is greatly appreciated!
