Apple's built-in disk management utility for the mac. Erases, formats, and restores volumes and drives.

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3k views

How to Create Images with Yosemite

I have a Mac Mini configured just the way I like it with 10.10.2 installed. I need to deploy that to a bunch of other computers around campus. The usual process for me in the past has been to use an ...
0
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1answer
118 views

Not enough free space on OS X Base System while installing El Capitan with VirtualBox

I am getting an error while installing OS on Virtual Box machine, that there is not enough free space as shown in the image. I allocated 20GB while setting up virtual machine, and 8.8GB is what apple ...
2
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4answers
7k views

partition map check failed because no slices were found

I own an early 2011 MacBook Pro running Mac OS X Mavericks. Recently, I tried to make 50 GB partition using Disk Utility but the whole process didn't complete, and I had to restart the system as it ...
3
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10answers
33k views

Disk Utility won't allow me to delete and resize partitions

I'm running OS X 10.9, and I had a linux partition when I updated from 10.8. Since I updated I can't boot on linux, which is no big deal for me. However, I would like to delete the partition that is ...
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2answers
1k views

Can't Delete Partition

I created a partition to run Snow Leopard on my computer running El Capitan and no longer need it. I allocated 20GB to that partition. Here's what I've done. I first go into Disk Utility, select my ...
2
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1answer
2k views

How to create a Mac bootable gparted or Parted Magic thumb drive?

Is it possible to create a Mac-bootable thumb drive containing gparted or Parted Magic without installing a full Linux distribution? I tried several methods like unetbootin (some blogs suggest this ...
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4answers
74k views

How to resolve error: “Couldn't modify partition map because file system verification failed”?

I upgraded to Lion and decided I no longer want 100 GB of my drive devoted to Boot Camp, I never boot into Windows, I just use it as a VM anyways. So I deleted the boot camp partition using disk ...
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2answers
513 views

Disk Utility can't repair external hard drive, tried fsck whats the next step?

When I try and repair my external hard drives (I have two corrupt now some how both I think from improperly ejecting from the same machine), I get this message: Disk Utility can’t repair this ...
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2answers
712 views

How to remount external drive in OS X El Capitan without rebooting?

I have a MacBook Pro 15 Mid 2014 with OS X El Capitan. When I accidentally disconnect the external USB disk (without clicking eject), I can't reconnect the disk. If I remove and plug the disk back in ...
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3answers
133 views

Command line equivalent of Disk Utility, which is not diskutil, to obtain UUID

Following on from the answer to Can you make OSX mount just certain partitions when you connect an external HDD?, all of the sites that I have checked (CNET, OSXDaily, Apple Support community threads) ...
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1answer
127 views

How do I pass the following error message in the Boot Camp Assistant: “Please format the USB drive as single FAT partition.”?

I am running the Boot Camp Assistant on El Capitan. Whenever I reach the third screen, titled "Save Windows Support Software", on which I can select an storage medium to save the Windows support ...
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13answers
176k views

How can I repair a disk that Disk Utility says it can't repair?

I have an external hard-disk with a single Mac OS Extended partition. This disk stopped working couple of days ago. I tried to repair the partition with disk utility but no luck. The error message is ...
2
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1answer
33 views

About This Mac > Storage shows 10GB Backups, but Time Machine is Disabled

I'm trying to figure out what's going on with my storage. About This Mac > Storage shows that there's ~11GB of Backups. Disk Utility seems to sort the same files as "Other". Googling tells me that ...
2
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3answers
2k views

Disk structure error reported in Onyx but not fixable via the Disk Utility in Recovery Mode

On Yosemite 10.10 Onyx returns the following error: Error: -69845: File system verify or repair failed Underlying error: 8: POSIX reports: Exec format error The disk needs to be repaired. I ...
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1answer
26 views

OS X Disk Utility shows more data

On OS X El Capitan Disk Utility shows me that I have 48 GB Movies, but I don't have this films really. Where can I find these movies that shows Disk Utility?
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0answers
62 views

Lost disk space after boot camp

The title is self explanatory, I lost disk space after a fatal Boot Camp manipulation. I deleted the Boot Camp partition, I did a fdisk -fy command and I ended with ~50 GB of unallocated disk space. ...
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0answers
11 views

Manually copy .ISO to bootable USB (without Bootcamp) [duplicate]

I want to create a bootable Windows USB from my Macbook manually as an alternative to Bootcamp. I've downloaded the Windows 10 ISO file. Formatted an 8GB USB with MS-DOS(FAT) with a Master Boot ...
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0answers
17 views

iMac partition grid screwed. Please help?

So yeah i guess i screwed up my iMac 5k retina's (late 2014) partition grid big time and i need your help. It all started yesterday when i tried to format my computer. I'm selling it tomorrow, that's ...
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0answers
13 views

Boot Camp says there is a partition when there isnt one

My boot camp is keeping me from using it because it says there is more than one partition (which i may or may not have made in the past). When i go into the disk utility it only shows the internal ...
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4answers
190 views

El-capitan crashing while booting

Objective: Somehow I want to fix the issue and should be able to login to the El-Capitan without reformating as so many valuable files are there Find what has caused this problem so that I can avoid ...
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0answers
96 views

Missing space in OS X El Capitan after removing a failed Boot Camp partition

I'm trying to help my girlfriend after a failed Boot Camp partition removed approx. 100 GB of visible space from her OS X volume. The main volume is encrypted with FileVault2. Partition table: ...
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2answers
61 views

Mount all mountable partitions of a removable disk with diskutil

I have a USB drive containing 2 FAT partitions which are automatically mounted when the drive is plugged in. If I run diskutil unmounDisk <device> and then diskutil mountDisk <device> I'd ...
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1answer
138 views

Unmounted hard drive times out ejecting or mounting

I have a Drobo connected via Firewire to my MBP which is causing me some issues. Here is the diskutil info: Device Identifier: disk2s2 Device Node: /dev/disk2s2 Whole: ...
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1answer
51 views

Disk image of OS + Recovery partition?

I'm working with multiple OS X versions frequently and I'd like to have an image which contains a particular OS version's system partition and its recovery partition. Is this possible? (the disk where ...
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2answers
66 views

Prohibited sign - Can't boot after trying to open Raspian SD Card

So I was following this tutorial https://www.youtube.com/watch?v=Eo4HphBdR10 and opened the folder of the SD Card. The Screen went black and I rebooted. Now I get a Prohibited Sign on boot up. In ...
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1answer
88 views

Cannot reformat external drive with no file system

This whole mess started with trying to encrypt Time Machine backups. I have a 4TB Lacie P9230 external drive which has been working for about a year just fine. The drive has been partitioned into two ...
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1answer
54 views

El Capitan Resize VM Partition

So I have this VM in my VMware Fusion, I add 5GB of space to the HDD but then I got this message saying resize the partition: But when I login to my VM and launch Disk Utility, I am not seeing the ...
2
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1answer
3k views

Fixing a broken hard drive's partition map

I have a drive that is corrupted. Disk utility could not repair the disk, so I attempted to follow some tutorials and repair the partitions using pdisk and testdisk, but things have gone south. Now ...
2
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1answer
30 views

Error while unpartitioning hard drive?

I've tried to install Ubuntu (and gave up), but now there's a stuck partition, of 24.22 gigabytes. The pink shows the partition. I want to unpartition it, but when I try to delete it, an error ...
25
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3answers
29k views

How do I get detailed SMART disk information on OS X (Mavericks or later)

I'm trying to get a detailed SMART status report on the drives in my Mac. I'm not talking about "Verified," I'm talking about the detailed report that's about 100 lines long listing all the vital ...
1
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1answer
31 views

Is it possible to get the text log for Disk Utility First Aid check?

Does/can the standard Disk Utility in OS X (El Capitan) log the "First Aid" disk check results in text file? Copy paste does not work on this control and to record the whole log I had to take 22 ...
2
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1answer
1k views

Accidently deleted some small sized partitions when installing WIndows(Bootcamp). OSX Partition wont boot

I tried to install Windows 8 into my Mac via Bootcamp. I booted into the Windows 8 Installer and had issues formatting the drive that I partitioned for the OS. Like an idiot, I deleted all of the ...
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0answers
15 views

Unable to reformat USB drive used for El Captian boot disk

I finally got a USB drive (PNY 128 GB) as an installer for El Capitan using instructions from Frakes' article in MacWorld. The installer seemed to work but I halted the installation process. When I ...
3
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1answer
48 views

External hard drive disconnected during reformat: now will not format

Using disk utility, I was erasing and re-formatting to FAT. During that process, the usb cable was removed. Now, the hard drive will not format. When recognizing the hard drive, a window shows up ...
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0answers
40 views

“Your startup disk is almost full.” message appears but the available space is ~60G

I have enough available space as shown in the attached image but the message "Your startup disk is almost full." appears when I save files. Also my MacBook Air is slow and buffering when I print a ...
12
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4answers
78k views

Disk Utility won't Unmount HD for formatting

I have two internal drives in my 27" iMac (10.8.5). An SSD system disk and a 1TB SATA drive. The HDD has been acting up recently, very slow performance, bad behavior etc. Tech Tool Pro and Disk ...
2
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1answer
810 views

Can't erase unmountable external HD

My external HD isn't mounted and can't be repaired by Disk Utility. However, I'm also unable erase the disk: $ diskutil list disk2 /dev/disk2 #: TYPE NAME ...
1
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1answer
90 views

How can I fix Error: -69877: Couldn't open device after interrupted formatting process?

This question, possibly the same question, has been asked: Couldn't open device However, my question hopefully demonstrates a more specific scenario as the situation in which caused the error ...
5
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2answers
164 views

How to fix Mac hard drive partition showing as Fdsik_partition_scheme

My situation seems very similar to how to fix GUID hard drive corrupted to MBR but with enough differences that I haven't been able to put together a confident solution. I have a 3TB Toshiba drive in ...
2
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3answers
12k views

Disk Utility vs Carbon Copy Cloner - How to clone your drive with Apple's built-in app

What is the point of using commercial apps like Carbon Copy Cloner when disk utility can also clone your drives? This article here ...
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0answers
33 views

Cannot Repair Macintosh HD, after loading into OSX, it become a [X]

When i restart the computer and loading with the apple logo, wait for few second, and the apple icon become [x] My Mac is OSX EL Capitan (v10.11.3) I used Disk Utility "First Aid" and found that ...
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2answers
1k views

Equivalents for genisoimage and qemu-img on Ubuntu

How do I achieve the same result on OS X 10.9 as I do on Ubuntu with commands: $ genisoimage -output init.iso -volid cidata -joliet -rock user-data meta-data and $ qemu-img convert -O raw disk.img ...
12
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4answers
5k views

How much data has been written to my SSD over its lifetime?

Is there a Terminal command which will show me how many GB has been written to my SSD through the whole lifetime of the disk? I'm asking because I want to find out how many cycles have been done. SSD ...
2
votes
3answers
18k views

Changing a Volume's “Device / Media Name”

I know a Mac volume can be renamed... obviously. But if you look at the output of diskutil you will see that a volume also has a "device name" that corresponds to the name it was given when it was ...
0
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1answer
78 views

OS X 10.11 Disk Utility, encrypted dmg password and keychain

In previous versions of Disk Utility there were checkboxes whether to store the password in the keychain or not while creating an encrypted dmg image. Now there are less options. Does the new version ...
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0answers
20 views

Might have spoiled the flash drive while trying to create a bootable disk on Yosemite

Basically I was following the steps given in the following site: How to create a bootable USB stick on OS X I did not get a screenshot of the terminal, but when going through step 8, it was ...
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6answers
23k views

How to identify and fix files with corrupted / inaccessible disk blocks

I have a late 2011 Macbook Pro, running Mavericks 10.9.2. Its sole HDD is a 750GB drive, formatted with Bootcamp. It's still running reasonably well, but in running a defragment pass on it, I've ...
6
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2answers
61k views

What are next steps when fsck reports “could not be repaired after 3 attempts”?

My Mac Book Pro 13.-" doesn´t get past the grey booting screen with the apple and the spinning wheel (The loading bar appears but when it´s done nothing happens) I have 220 GB in one single ...
2
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1answer
14k views

Disk Utility message “Updating boot support partitions for the volume as required”

Finder crashed on a external drive which caused an abrupt eject. I rand Disk Utility over the drive and the operation finished with the message: Updating boot support partitions for the volume as ...
4
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3answers
10k views

Mount Ext4 on El Capitan

I recently installed OS X 10.11 on my Mac. I tried to read a SD card with an Ext4 partition which wasn't even shown in Disk Utility, although diskutil did show it as a Linux partition. I can't seem ...