Q: Can't format former Boot Camp partition

Your GPT and Fdisk does not show what Disk Utility shows. Can you boot in Safe Mode and boot normally and check Disk Utility?

Try safe mode if your Mac doesn't finish starting up - Apple Support

The computer has refused to boot normally. It boots only under safe mode. While trying to boot normal it shows only a black screen with circle at the center.

Then under safe mode, it shows that a partition of 120GB (fusion drive I think) is under error is asking me to fix it. Fixing it will wipe out everything in the system and I have to recover using time machine.  Should I fix?

The following is the list I got from safe mode terminal. As it is now, It does not boot in normal OS X environment. I am waiting for the next step forward.

-bash-3.2# diskutil list

/dev/disk0

  #: TYPE NAME SIZE IDENTIFIER

  0: GUID_partition_scheme *121.3 GB disk0

  1: EFI EFI 209.7 MB disk0s1

  2: Apple_CoreStorage 121.0 GB disk0s2

  3: Apple_Boot Boot OS X 134.2 MB disk0s3

/dev/disk1

  #: TYPE NAME SIZE IDENTIFIER

  0: GUID_partition_scheme *1.0 TB disk1

  1: EFI EFI 209.7 MB disk1s1

  2: Apple_HFS 999.3 GB disk1s2

  3: Apple_Boot Recovery HD 650.0 MB disk1s3

/dev/disk2

  #: TYPE NAME SIZE IDENTIFIER

  0: Apple_partition_scheme *1.3 GB disk2

  1: Apple_partition_map 30.7 KB disk2s1

  2: Apple_HFS OS X Base System 1.3 GB disk2s2

/dev/disk3

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *5.2 MB disk3

/dev/disk4

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk4

/dev/disk5

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk5

/dev/disk6

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk6

/dev/disk7

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk7

/dev/disk8

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk8

/dev/disk9

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *6.3 MB disk9

/dev/disk10

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *2.1 MB disk10

/dev/disk11

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *1.0 MB disk11

/dev/disk12

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk12

/dev/disk13

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *524.3 KB disk13

/dev/disk14

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *1.0 MB disk14

/dev/disk15

  #: TYPE NAME SIZE IDENTIFIER

  0: untitled *6.3 MB disk15

-bash-3.2#

-bash-3.2# diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group 466ADA0E-F91D-41F0-A544-A0496D3AB698

  =========================================================

  Name: OSX-MacintoshLVG

  Status: Offline

  Size: 120988852224 B (121.0 GB)

  Free Space: -none-

  |

  +-< Physical Volume 7C80F65C-A801-4DB6-9642-5E2568B310AC

  | ----------------------------------------------------

  | Index: 0

  | Disk: disk0s2

  | Status: Checking

  | Size: 120988852224 B (121.0 GB)

  |

  +-< Physical Volume D0291C1F-EB90-4289-B34A-0C79DF081B5B

  ----------------------------------------------------

  (No properties)

-bash-3.2#

-bash-3.2# sudo gpt -vv -r show /dev/disk0

-bash: sudo: command not found

-bash-3.2# gpt -vv -r show /dev/disk0

gpt show: /dev/disk0: mediasize=121332826112; sectorsize=512; blocks=236978176

gpt show: /dev/disk0: PMBR at sector 0

gpt show: /dev/disk0: Pri GPT at sector 1

gpt show: /dev/disk0: Sec GPT at sector 236978175

  start size index contents

  0 1 PMBR

  1 1 Pri GPT header

  2 32 Pri GPT table

  34 6 

  40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

  409640 236306352 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

  236715992 262144 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

  236978136 7 

  236978143 32 Sec GPT table

  236978175 1 Sec GPT header

-bash-3.2# fdisk /dev/disk0

Disk: /dev/disk0 geometry: 14751/255/63 [236978176 sectors]

Signature: 0xAA55

  Starting Ending

#: id cyl hd sec - cyl hd sec [ start - size]

------------------------------------------------------------------------

1: EE 1023 254 63 - 1023 254 63 [ 1 - 236978175] <Unknown ID>

2: 00 0 0 0 - 0 0 0 [ 0 - 0] unused 

3: 00 0 0 0 - 0 0 0 [ 0 - 0] unused 

4: 00 0 0 0 - 0 0 0 [ 0 - 0] unused 

-bash-3.2# gpt -vv -r show /dev/disk1

gpt show: /dev/disk1: mediasize=1000204886016; sectorsize=512; blocks=1953525168

gpt show: /dev/disk1: PMBR at sector 0

gpt show: /dev/disk1: Pri GPT at sector 1

gpt show: /dev/disk1: Sec GPT at sector 1953525167

  start size index contents

  0 1 PMBR

  1 1 Pri GPT header

  2 32 Pri GPT table

  34 6 

  40 409600 1 GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B

  409640 1951845952 2 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

  1952255592 1269536 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

  1953525128 7 

  1953525135 32 Sec GPT table

  1953525167 1 Sec GPT header

-bash-3.2# fdisk /dev/disk1

Disk: /dev/disk1 geometry: 121601/255/63 [1953525168 sectors]

Signature: 0xAA55

  Starting Ending

#: id cyl hd sec - cyl hd sec [ start - size]

------------------------------------------------------------------------

1: EE 1023 254 63 - 1023 254 63 [ 1 - 1953525167] <Unknown ID>

2: 00 0 0 0 - 0 0 0 [ 0 - 0] unused 

3: 00 0 0 0 - 0 0 0 [ 0 - 0] unused 

4: 00 0 0 0 - 0 0 0 [ 0 - 0] unused 

-bash-3.2#

diskutil cs list

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group 466ADA0E-F91D-41F0-A544-A0496D3AB698

  =========================================================

  Name: OSX-MacintoshLVG

  Status: Offline

  Size: 120988852224 B (121.0 GB)

  Free Space: -none-

  |

  +-< Physical Volume 7C80F65C-A801-4DB6-9642-5E2568B310AC

  | ----------------------------------------------------

  | Index: 0

  | Disk: disk0s2

  | Status: Checking

  | Size: 120988852224 B (121.0 GB)

  |

  +-< Physical Volume D0291C1F-EB90-4289-B34A-0C79DF081B5B

  ----------------------------------------------------

  (No properties)

This is not a good sign.

The following step may break the current volume requiring a full CS rebuild and TM restore.

diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79DF081B5B

diskutil cs removeDisk

Usage:  diskutil coreStorage removeDisk pvUUID

Remove a physical volume from its CoreStorage logical volume group.

Ownership of the affected disks is required.

Example: diskutil coreStorage removeDisk 11111111-2222-3333-4444-555555555555

If the remove is successful, then check

diskutil list disk1

you can add it back to the LVG as

diskutil cs addDisk 466ADA0E-F91D-41F0-A544-A0496D3AB698 disk1s2

diskutil cs addDisk

Usage:  diskutil coreStorage addDisk lvgUUID NewMemberDeviceName

Add a new physical volume to a CoreStorage logical volume group.

Ownership of the affected disks is required.

Example: diskutil coreStorage addDisk

         11111111-2222-3333-4444-555555555555 disk4s2

in trying to remove the volume this is what I got

-bash-3.2# diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79Df081B5B

Error removing CoreStorage Physical Volume: Not a valid CoreStorage Physical Volume UUID (-69777)

-bash-3.2# diskutil cs removeDisk

Usage:  diskutil coreStorage removeDisk pvUUID

Remove a physical volume from its CoreStorage logical volume group.

Ownership of the affected disks is required.

Example: diskutil coreStorage removeDisk 11111111-2222-3333-4444-555555555555

-bash-3.2# RalphImac

-bash: RalphImac: command not found

-bash-3.2# diskutil coreStorage removeDisk D0291C1F-EB90-4289-B34A-0C79Df081B5B

Error removing CoreStorage Physical Volume: Not a valid CoreStorage Physical Volume UUID (-69777)

-bash-3.2#

The quoted text show the syntax of the command. It is not meant to be executed.

diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79Df081B5B

does not match

diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79DF081B5B

Try with an uppercase (F081B5B) rather than (f081B5B). I have found quite a few difference when used CS commands in Recovery Console vs normal OS X.

It continues to show the same error. I even went online using safari online help to log in to our discussion and copied the Disk number using command c. I came back to terminal and pasted it using Command V.

-bash-3.2# diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79DF081B5B

Error removing CoreStorage Physical Volume: Not a valid CoreStorage Physical Volume UUID (-69777)

-bash-3.2#

-bash-3.2# diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79DF081B5B

Error removing CoreStorage Physical Volume: Not a valid CoreStorage Physical Volume UUID (-69777)

-bash-3.2#

-bash-3.2# diskutil cs removeDisk D0291C1F-EB90-4289-B34A-0C79DF081B5B

Error removing CoreStorage Physical Volume: Not a valid CoreStorage Physical Volume UUID (-69777)

-bash-3.2#

Do you have a good OS X backup? We need to nuke-and-pave.

I opened disk utility and it shows me that a part of the disk 120GB (fusion drive I think) needs to be fixed. It is asking for permission to fix it. It says "This fusion drive is missing a disk. Would you like to rebuild this Fusion Drive?" It continues "Rebuilding will erase the following disks: disk0s2.

Can this process give us the same result since Terminal command is not working?

yes I have my Samsung 1 TB connected to TM. I disconnected it before downloading the gpt Fdisk.

ralphejims wrote:

 

I opened disk utility and it shows me that a part of the disk 120GB (fusion drive I think) needs to be fixed. It is asking for permission to fix it. It says "This fusion drive is missing a disk. Would you like to rebuild this Fusion Drive?" It continues "Rebuilding will erase the following disks: disk0s2.

 

Can this process give us the same result since Terminal command is not working?

Yes, please try and see if it will fix it automatically.

Can you start a new discussion, so we can leave this one behind? It is very hard to read.

I allowed the command to fix it through disk utility. it showed me that it has fixed. However, it deleted the entire disk. I tried to restart it but it is going through internet recovery now. It will take few minutes. I will post the details of the disk after internet recovery. Give me the commands you will like me to check through terminal if OS X will not load automatically. However I suspect I have to go through TM recovering connecting External drive in order to recover OS X. Give me the commands.

I have created anew discussion "Partition problem while install windows 8.1pro on my Imac using boot camp." The internet recovery has finished. Waiting for you for the next step forward.

Hello Loner T, I just created a new thread with a very similar problem, I would very much appreciate your help on this.

Can't format drive after Bootcamp

Many, many thanks in advance!