Cant use free space. Couldn't read partition map (-69876)

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Cant use free space. Couldn't read partition map (-69876)

Hi all,

just bought a new iMac 27" with 512 SSD. After bootcamp failed to install i did a reboot. Unfortunately bootcamp would not want to reinstall. Checking Disk Utility showed free space in the partition table. I can not delete it ( error code Couldn't read partition map (-69876)) so i'm kinda stuck now with 1 gb off free space that not allows me to use it and prevents bootcamp from installing Message:

The startup disk must be formatted as a single Mac OS Extended (Journaled) volume or already partitioned by Boot Camp Assistant for installing Windows.

Around 100gb available for bootcamp but this cannot be merged to 1 disk as required...

diskutil list:

/dev/disk0 (internal, physical):

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *500.3 GB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_CoreStorage Macintosh HD 399.4 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Apple_HFS NewName 99.4 GB disk0s4

/dev/disk1 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +399.0 GB disk1

Logical Volume on disk0s2

3DB995B0-D676-471E-839C-571916143CA0

Unencrypted

Please advise what to do.

Many thanks.

Lennart

iMac with Retina 5K display, OS X El Capitan (10.11.2), failed bootcamp

Posted on Dec 23, 2015 7:26 PM

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Answer 1

Nubz N.

Community Moderator

Dec 25, 2015 7:29 AM in response to LVISnl

Hi Lennart,

I understand you want to intsall Windows with Boot Camp but for some reason it failed and now you can't seem to unify the hard disk again with Disk Utility.

Note when you partition the hard drive with Boot Camp you need to remove the partitions with Boot Camp.

From Set up a Windows partition on your Mac - Apple Support

Remove the partition

Use Boot Camp Assistant to safely remove Windows and the Windows partition from your Mac, restoring your startup drive to a single Mac partition. You may want to back up your information first, because removing the partition erases all of the data it contains.

Open Boot Camp Assistant.

Select “Remove Windows 7 or later version," then click Continue.

Do one of the following:

If your Mac has a single internal disk, click Restore.

If your Mac has multiple internal disks, select the Windows disk, select “Restore disk to a single OS X partition,” then click Continue.

For more details, please see

Boot Camp: Solve partition creation problems

How to install Windows using Boot Camp - Apple Support

Boot Camp: Solve Windows installation problems

Best regards.

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Answer 2

Loner T

Level 9

59,536 points

Dec 25, 2015 7:46 AM in response to LVISnl

BC Assistant has reduced the OS X volume, but failed to create the BC/Windows part. Please see Lost storage space on my mac for possible recovery methods.

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