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How to fix guid partition table?

I was trying to install Bootcamp on El Capitan. When it got to "Partitioning disk..." my Mac kernel panicked, rebooted, and now I have a "Basic Data" partition which can't be removed because Disk Utility says "Counldn't read partition map..." and if I try to run first aid it says that there are problems in the partition map that may prevent my computer from booting. I'm too scared to reboot because of that error. What can I do? This is what diskutil list says:

/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 400.3 GB disk0s2

3: Apple_Boot Recovery HD 784.2 MB disk0s3

4: Microsoft Reserved 134.2 MB disk0s4

5: Apple_HFS Basic Data 98.7 GB disk0s5

/dev/disk1 (internal, virtual):

#: TYPE NAME SIZE IDENTIFIER

0: Apple_HFS Macintosh HD +400.0 GB disk1

Logical Volume on disk0s2

5DE93344-5DC0-47A1-A1C7-BB44BD5AC046

Unlocked Encrypted


and here is gpt show:

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 781905368 2 GPT part - 53746F72-6167-11AA-AA11-00306543ECAC

782315008 1531680 3 GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC

783846688 736

783847424 262144 4 GPT part - E3C9E316-0B5C-4DB8-817D-F92DF00215AE

784109568 192733312 5 GPT part - 48465300-0000-11AA-AA11-00306543ECAC

976842880 262147

977105027 32 Sec GPT table

977105059 1 Sec GPT header

Can somebody help? I'm doing a backup right now to prevent data loss.

Posted on Nov 29, 2015 11:47 AM

Reply
3 replies

Nov 29, 2015 4:25 PM in response to AppleFred2012

The simplest and safest method to get your disk space back is


1. Backup OSX and all your files - Use Time Machine to back up or restore your Mac - Apple Support .

2. Boot into Internet Recovery (Command+Opt+R) - OS X: About OS X Recovery - Apple Support .

3. Click on Utilties -> Disk Utility and Erase your internal whole disk.

4. Restore OSX and your files - Use Time Machine to back up or restore your Mac - Apple Support .


This requires a separate external disk which can accommodate TM backup - Backup disks you can use with Time Machine - Apple Support .

How to fix guid partition table?

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