Error: -69879: Couldn't open disk

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Level 1

6 points

Error: -69879: Couldn't open disk

Hi all, having a bit of a nightmare recently thanks to Yosemite update 😟.

I have a 2007 iMac which has a 1TB HDD partitioned (750 Mac, 250 Windows XP). Over the past 2 years my Mac side was sluggish and freezing constantly, it improved slightly by Mavericks and I also upgraded the RAM. Yosemite seemed even better and I thought it was coming back from the dead but after the most recent update the iMac will reboot at about 50% load during boot. I was stuck.

Luckily I entered my XP partition and using some software backed up my important files from the Mac partition. I'm now free to erase the Mac partition and reinstall the OS, hoping it'll appreciate the clean start after all these years. I first thought the hard-drive was dying due to the freezes but my XP partition runs superfast with no problems and it's on the same disk. Anyway, booting with CMD + R and entering Disk Utility, the icon for the Mac partition is greyed out - I can't repair the disk or erase it right clicking and attempting to mount it fails also. When attempting to erase the volume via terminal using; 'diskutil eraseVolume JHFS+ Mac /dev/disk0s2' I get the error: -69879: Couldn't open disk.
Any other way I can format this without losing my Windows partition?

iMac, OS X Yosemite (10.10.2)

Posted on Feb 19, 2015 7:24 AM

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Answer 1

brgn Author

Level 1

6 points

Feb 20, 2015 8:12 AM in response to Linc Davis

Typedit out by hand as stated in previous post I can't copy to clipboard and then progress to a state where I can post it online. pbcopy command also didn't work as mentioned above. Hopefully the information provided below will suffice 🙂. Sorry about the formatting. Seems weird I have all these extra disks or odd sizes, these don't display in Disk Utility.

/dev/disk0

#: TYPE NAME SIZE IDENTIFIER

0: GUID_partition_scheme *1.0 TB disk0

1: EFI EFI 209.7 MB disk0s1

2: Apple_HFS Macintosh HD 782.1 GB disk0s2

3: Apple_Boot Recovery HD 650.0 MB disk0s3

4: Microsoft Basic Data .Windows XP 217.2 GB disk0s4

/dev/disk1

#: TYPE NAME SIZE IDENTIFIER

0: Apple_partition_scheme *1.3 GB disk1

1: Apple_partition_map 30.7 KB disk1s1

2: Apple_HFS OS X Base System 1.3 GB disk1s2

/dev/disk2

#: TYPE NAME SIZE IDENTIFIER

0: untitled *5.2 MB disk2

/dev/disk3

#: TYPE NAME SIZE IDENTIFIER

0: untitled *524.3 KB 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 *6.3 MB disk8

/dev/disk9

#: TYPE NAME SIZE IDENTIFIER

0: untitled *2.1 MB disk9

/dev/disk10

#: TYPE NAME SIZE IDENTIFIER

0: untitled *1.0MB disk10

/dev/disk11

#: TYPE NAME SIZE IDENTIFIER

0: untitled *524.3 KB disk11

/dev/disk12

#: TYPE NAME SIZE IDENTIFIER

0: untitled *524.3 KB disk12

/dev/disk13

#: TYPE NAME SIZE IDENTIFIER

0: untitled *1.0 MB disk13

/dev/disk14

#: TYPE NAME SIZE IDENTIFIER

0: untitled *6.3 MB disk14

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Answer 2

Oct 4, 2016 6:15 PM in response to brgn

I have a WD Elements with 1TB capacity and every time if I do not ejected the disk properly then I couldn't access the disk via Finder anymore. I found that the disk was not unmounted properly, hence I have tried the following and it works after.

1) Run the disk utility from MAC application and you should be able to see your disk's volume and partition.

2) Use the info in the command bar at the top and find out which disk number for your disk, eg. Disk2

3) Use the Terminal command from the MAC application.

4) Enter the command "diskutil unmountdisk /dev/disk2"

5) And once it is unmounted the whole volume properly, you can then access your disk via the Finder...

Good luck!

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Answer 3

Linc Davis

Level 10

209,739 points

Feb 19, 2015 2:07 PM in response to brgn

This procedure is a diagnostic test. It makes no changes to your data.

Please enter this command:

{ diskutil list; echo; diskutil cs list; } | pbcopy

The output will be automatically copied to the Clipboard. If the command produced no output, the Clipboard will be empty. Paste into a reply to this message.

If any personal information appears in the output, anonymize before posting, but don’t remove the context.

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Answer 4

brgn Author

Level 1

6 points

Feb 20, 2015 2:14 AM in response to Linc Davis

Hi Linc, thanks for the help!

When i enter the exact command above I get the following result:

pbcopy: command not found

Unfortunately as I can't see a way to paste it to here from the clipboard (i'm unable to log in after CMD+R).
I've tried the command above without | pbcopy and this is the result:

http://www.arekkz.com/burgon/macpartitions.JPG

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Answer 5

Linc Davis

Level 10

209,739 points

Feb 20, 2015 8:39 AM in response to brgn

First, running Windows XP in Boot Camp under Yosemite is not supported.

You'll need to boot from another drive in order to repartition the startup drive. All data on the drive, including Windows data, will be removed. You can use your Snow Leopard installation disc for this purpose. Hold down the C key at the startup chime to boot from the disc, then launch Disk Utility. After partitioning the drive with the default options, install OS X. You'll then need to download the Yosemite installer from the App Store, if you want to run Yosemite. But on such old hardware, and especially if you want to run XP, you may be better off staying with Snow Leopard.

If you've lost the installation disc, you can order a replacement from Apple.

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Answer 6

Linc Davis

Level 10

209,739 points

Feb 20, 2015 7:32 AM in response to brgn

Please post the output of the command on this page as text, not a screenshot.

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