Can't partition my disk to install Windows 10 on

Question

Level 1

4 points

Can't partition my disk to install Windows 10 on

Hi all,

I get the "your disk could not be partitioned"-error when trying to partition my Fusion Drive into Macintosh HD on one side and the bootcamp W10-partition on the other side. I tried everything already suggested in other topics and elsewhere on the internet. I tried "/sbin/fsck -fy" in Single User Mode. I tried Disk Utlitity in Recovery Mode. I tried deleting all the snapshots via Terminal. I tried First Aid-mode in either DU in normal mode as well as in recovery mode. I'm out of options. Please, help?

iMac, macOS High Sierra (10.13.6), late 2014 model

Posted on Jul 20, 2018 6:41 AM

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Answer 1

Loner T

Level 9

59,471 points

Jul 21, 2018 7:15 AM in response to Cav3ry

Boot into Internet Recovery using the procedure described in About macOS Recovery - Apple Support .

In Recovery Console, click on Utilities -> Terminal, and

Delete the CS LV - diskutil cs deleteVolume F69D3E0B-04CB-4979-A843-785D28A0976F
Delete the CS LVG - diskutil cs delete BCB85BDD-193E-4B4E-BC7B-CA01188FE633
Erase the SSD (121GB) and HDD (1TB) -
1. disktuil eraseDisk jhfs+ SSD disk0
2. diskutil eraseDisk jhfs+ HDD disk1
Re-create the CS LVG
1. diskutil cs create "Macintosh-LVG" disk0s2 disk1s2
2. The previous command will generate a CS LVG UUID, similar to the string in step 2
Re-create the CS LV using the UUID string created in step 4.1. You need to replace the "quoted" string by the actual value.
diskutil cs createVolume "UUIDFromStep4.1" jhfs+ "Macintosh HD" 100%
Post the output of diskutil cs list for verification
Now restore your TM Backup
Post the output of diskutil cs list for verification
Re-try your BC Assistant steps and post any error messages

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Answer 2

Cav3ry Author

Level 1

4 points

Jul 22, 2018 5:56 PM in response to Loner T

OK, I’m a little stressed now. It doesn’t show the Apple-logo anymore. I canMt do anything. It only shows this folder. Will post a diskutil in a sec.

Do I have to re-install from recovery mode? I just thought of that.

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Answer 3

Cav3ry Author

Level 1

4 points

Jul 24, 2018 4:58 AM in response to Loner T

So a bootcamp worked now. Found out the size of the BC-partition was too small for me (50 Gb, shuld've been 100Gb at least). Apparently there isn't an easy way to resize this due to the NTFS-structure of the BC-partition (duh). Googled the best way to do it, and am following the alternative procedure of https://www.partitionwizard.com/partitionmagic/reszie-boot-camp-partition.html#h owto-resize using MiniTool Partition Wizard. I'm now stuck in Disk Utility. Just made a Untitled free space in ExFAT-structure and now it's stuck during "changing size physical Core Storage-volumestructure. It's been saying this for 15 minutes now. Any idea what I could do?

I'm afraid to "force stop". it, but it there anything else I could do?

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Answer 4

Loner T

Level 9

59,471 points

Jul 20, 2018 6:36 PM in response to Cav3ry

In your diskutil list output, you can see disk0 and disk1, which are 'fused' together to build a single logical drive.

Can you use Re: Disk cannot be partitioned error! as an example to rebuild your Fusion drive? Steps 1 and 2 require the UUID values from your specific diskutil cs list output.

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Answer 5

Loner T

Level 9

59,471 points

Jul 20, 2018 4:26 PM in response to Cav3ry

Notice the size of disk1s3 - 126GB - which is due to bug in BC Assistant under High Sierra and CoreStorage volumes/groups (aka Fusion) drives.

Do you have a Time Machine backup of macOS? If not, can you create one on an external disk now.

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Answer 6

Loner T

Level 9

59,471 points

Jul 20, 2018 4:41 PM in response to Cav3ry

If you have a 1-1.5TB external disk that you can format and use for a macOS backup, it should be sufficient. The larger the external disk, the better. Once you finish backup, we need to erase both internal disks, and rebuild the Fusion drive.

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Answer 7

Cav3ry Author

Level 1

4 points

Jul 20, 2018 7:14 PM in response to Loner T

diskutil cs deleteVolume didn't work with right parameter "33EADDE3-60EA-4352-A922-19C1E187DDAE". Help? Can't go further now. It says: "33EADDE3-60EA-4352-A922-19C1E187DDAE does not appear to be a valid Core Storage Logical Volume UUID or disk".

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Answer 8

Cav3ry Author

Level 1

4 points

Jul 21, 2018 6:13 AM in response to Loner T

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group BCB85BDD-193E-4B4E-BC7B-CA01188FE633

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

Name: Macintosh HD

Status: Online

Size: 994855346176 B (994.9 GB)

Free Space: 114688 B (114.7 KB)

|

+-< Physical Volume 420CBF19-108B-46C3-80A2-0D0C4C3A8645

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

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 120988852224 B (121.0 GB)

|

+-< Physical Volume 33EADDE3-60EA-4352-A922-19C1E187DDAE

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

| Index: 1

| Disk: disk1s2

| Status: Online

| Size: 873866493952 B (873.9 GB)

|

+-> Logical Volume Family 1DDCD4A1-1609-483A-810F-DB90D6CE2EC7

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

Encryption Type: None

|

+-> Logical Volume F69D3E0B-04CB-4979-A843-785D28A0976F

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

Disk: disk2

Status: Online

Size (Total): 988999974912 B (989.0 GB)

Revertible: No

LV Name: Macintosh HD

Volume Name: Macintosh HD

Content Hint: Apple_HFS

LVG Type: Fusion, Sparse

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Answer 9

Loner T

Level 9

59,471 points

Jul 22, 2018 6:20 PM in response to Cav3ry

Yosemite should be the original OS the Mac cam with. Let it install macOS. One positive thing is that the disk should be in the correct layout, otherwise Yosemite would not install. Please let the installation finish.

If you have a purchased version of macOS, you can download it from the App Store and upgrade the Mac to that version.

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Answer 10

Cav3ry Author

Level 1

4 points

Jul 23, 2018 5:11 AM in response to Loner T

As requested. 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_CoreStorage 999.3 GB disk1s2

3: Apple_Boot Recovery HD 650.0 MB disk1s3

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD *1.1 TB disk2

Logical Volume on disk0s2, disk1s2

664598A6-3B11-4319-A043-EE4271A20AAF

Unencrypted Fusion Drive

------

I'm updating to High Sierra now. Will it do any harm if I perform a clean re-install High Serria after the update to it? That's kind of a habit from me. If macOS updates to a new version, I always perform a clean re-install.

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Answer 11

Cav3ry Author

Level 1

4 points

Jul 24, 2018 6:04 AM in response to Loner T

Had to puzzle a bit 'cause the IDs of the Volume and LVG were different. Think I did a good job though. Here's the output:

CoreStorage logical volume groups (1 found)

|

+-- Logical Volume Group F8089019-AC49-4CEA-9B49-CA55E0F9F5BD

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

Name: Macintosh-LVG

Status: Online

Size: 1120849764352 B (1.1 TB)

Free Space: 0 B (0 B)

|

+-< Physical Volume C6886694-D881-4B41-BEDF-4B7F6B1354E9

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

| Index: 0

| Disk: disk0s2

| Status: Online

| Size: 120988852224 B (121.0 GB)

|

+-< Physical Volume 83B4D33D-ACE9-40A7-B0E1-8BB766679ACB

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

| Index: 1

| Disk: disk1s2

| Status: Online

| Size: 999860912128 B (999.9 GB)

|

+-> Logical Volume Family 8AE3933B-4E79-4990-9759-422E1689F548

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

Encryption Type: None

|

+-> Logical Volume 367D7862-3681-42EA-91EA-1E396FD9576C

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

Disk: disk3

Status: Online

Size (Total): 1114994507776 B (1.1 TB)

Revertible: No

LV Name: Macintosh HD

Volume Name: Macintosh HD

Content Hint: Apple_HFS

LVG Type: Fusion, Sparse

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Answer 12

Cav3ry Author

Level 1

4 points

Jul 24, 2018 5:13 PM in response to Loner T

Actually, no. It re-installed High Sierra. I didn't shut down after deleting all volumes and such; I did shut down last down and saw that empty folder afterwards when starting up my Mac. I immediately re-installed macOS after deleting the LVG and volumes. Is that a prloblem (that it installed High Sierra and not Yosemite)?

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Answer 13

Cav3ry Author

Level 1

4 points

Jul 27, 2018 5:42 AM in response to Loner T

Hey man, all looks good now, I guess. Windows installed perfectly! I do have, which I don't recall having before, along with my Macintosh HD and Bootcamp-disk, a Windows and EFI Boot disk to choose for at start-up holding the option-key. What about that?

Can I buy you a coffee somehow by the way?

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Answer 14

Loner T

Level 9

59,471 points

Jul 27, 2018 6:01 AM in response to Cav3ry

Cav3ry wrote:

Hey man, all looks good now, I guess. Windows installed perfectly! I do have, which I don't recall having before, along with my Macintosh HD and Bootcamp-disk, a Windows and EFI Boot disk to choose for at start-up holding the option-key. What about that?

If you have a Late 2015 or later Mac, the default method is EFI Boot, which shows up as an extra selection. A screen shot would be helpful. High Sierra prefers EFI over BIOS. Do both of the selection properly boot Windows?