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

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How to delete partition disk0s4?

A while ago, I dual booted with ubuntu linux and followed a tutorial on youtube to do so, but later I wanted all of my hard drive to be for osx, so I deleted the ubuntu partition, but now I am left ...
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1answer
42 views

GPT looks valid. Diskutil sees empty disk

External 3 TB disk. Stopped working after a power bump. GPT reports as follows: bash-3.2# gpt show /dev/disk6 start size index contents 0 1 PMBR ...
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1answer
45 views

Bootcamp Partition Creation Failure

I wanted to install Windows on my 2011 Macbook Air running 10.8. I had approximately 40 GB of a 120 GB hard drive free and I set Bootcamp to create a 20 GB partition for Windows. Halfway through the ...
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1answer
3k views

External HDD can be seen in Disk Utility but not in Finder

I've been using my external HDD a lot of times before on my Macbook Pro 13" OS X version 10.9.5, but it doesn't seem to appear in my Finder anymore. It can be seen in Disk Utility, though. Can anyone ...
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1answer
120 views

Disk Utility not letting me partition my SSD or modify the current ones

Just yesterday I finally got my hands on a MacBook Pro in which I was planning to install Ubuntu and Windows aside from OS X for studying purposes. I was barely beginning by partitioning the disk, or ...
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3answers
4k 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 ...
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1answer
51 views

Mac Encrypted HDD Please help!

Hi everyone I have encrypted a partition of an external hard drive from the mac desktop. I pressed that key button then pressed memorable and it changed my entire password unknowingly. I need help. ...
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1answer
1k views

Disk Utility won't let me create or resize partitions

My MacBook Pro 13" Late 2011 is running Yosemite. I am trying to install a Linux distribution on a partition of my hard drive. I used Disk Utility to resize the main partition on my hard drive and it ...
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1answer
58 views

Flashing question mark, low hard drive space

When I booted my Mac last night I got a flashing folder against a gray background. The computer started fine this morning, but when I closed the lid and opened it up again I had to reboot, and now ...
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0answers
124 views

Yosemite 'About this mac' displaying the wrong storage

I am having a strange problem where my 'About this mac' > ' Storage' is showing that I Have 470gb of Apps install on a 250gb SSD. I have used 3rd party disk scanners and they are all showing the ...
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3answers
623 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 ...
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1answer
184 views

How to add free space to a Logical Volume Group? (Resizing Partitions)

I have two CoreStorage volumes on disk, one is 200GB the other is 50GB. I want to make the 1st 125GB and the second one 125GB. Currently I have been able to use the diskutil cs resizeStack command to ...
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1answer
59 views

Remove Bootcamp when Boot Camp Assist will not

I purchased an iMac from a buddy and recently upgraded to Yosemite so I am learning as I go about Macs. However, I decided I wanted it to be quicker so I purchased an OWC SSD to install as a primary ...
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1answer
123 views

re expand a partitioned disk

The internal disk of my Mac book pro is partitioned as follows: % diskutil list /dev/disk0 #: TYPE NAME SIZE IDENTIFIER 0: ...
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1answer
83 views

“Couldn’t create temporary file.” error when erasing free space on external disk

I was trying to wipe the free space of an external USB 3.0 disk in OS X (Yosemite) disk utility. However, I receive the following error: EDIT: The disk is formatted as GUID / Mac OS Extended ...
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1answer
108 views

Macintosh HD disappeared from finder after “disk damaged and cannot be repaired”

I have a MacPro 13.3 Inch mid2011 with 500GB storage and recently while performing a Mac update, it froze and was still stuck on a grey screen even after multiple restart attempts. I finally tried ...
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1answer
3k views

How to reformat/install new SSD on MBP late2010 using OS X Internet Recovery

I had been saving some money to buy an SSD and finally I did. My old HDDs motor shut down so I had to replace it. I put it in the macbook all good but it isnt recognized by the system as a hard drive ...
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1answer
202 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 ...
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2answers
964 views

Erasing partition doesn't give me free diskspace

I'm using a Macbook Air and until today I had two partitions on it (not counting the restore partition). I had my OSX partition and an Ubuntu partition. As I don't use Ubuntu anymore, I decided to ...
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5answers
5k views

Disk Utility hangs prior to resizing partition

When trying to shrink the size of a partition, the period before the actual resizing happens (where Disk Utility says "Preparing to partition disk") hangs forever. I dug into Console to see what was ...
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2answers
40 views

Created a second OS X partition, erased the first, now can't delete old partition

I bought a secondhand macbook pro (early 2011). It was running Yosemite, but I wanted to do a fresh install, as initially I didn't have the password. I created a 2nd partition and installed a clean ...
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3answers
19k views

OS X Yosemite installation error: File system verify or repair failed

My Mac has been running fine until I decided to upgrade to OS X 10.10, Yosemite. When it is installing I get the message: File system verify or repair failed. I clicked the restart option to ...
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3answers
9k 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 ...
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0answers
146 views

Resizing and moving OSX partitions in Disk Utility

So, I have a Mac Mini with a 160GB drive (it's an old model but it's only for testing). It had 4 versions of OSX on it but one needed more space so I removed the oldest version (Lion) and want to keep ...
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1answer
968 views

diskutil eraseDisk results in Error: 12: POSIX reports: Cannot allocate memory

I'm trying to format my usb drive that is partitioned with FAT32 by the following command in Terminal: $ diskutil eraseDisk JHFS+ UntitledUFS disk1 However, I get this output: Started erase on ...
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4answers
1k views

Why does RAID 1 “Mirroring not provide performance improvements”?

I have always used Software RAIDs, either Apple-provided, or via SoftRAID, etc. I am about to re-zhuzh my arrays and decided to do a little research beforehand… and On Apple's site, there is a ...
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2answers
44 views

Resizing Partitions

I cannot resize the HD of a new Mac Mini. The Mac HD shows 700+ GB on one partition with Yosemite on it and another partition of 200+ GB named "Free Space" and I cannot figure out how it got there. ...
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2answers
202 views

Orphaned inodes in SSD in MacBook Pro Early 2011

I have a Macbook Pro 15″ Early 2011. Last year I changed the disk to put a new Samsung SSD (Evo). Recently my computer was really slow. I rebooted on the recovery partition, and tested my disk with ...
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1answer
61 views

I'm not able to re-size a HD Partition to utilize all its free space, how can I fix this?

I've seen a couple of questions on the exchange that are similar to the issues I am having. But I haven't been able to get things to work referencing those issues. I am ultimately looking to install ...
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10answers
64k views

How can I repair a disk that disk utility says it can't repair this disk?

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 ...
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1answer
312 views

diskutil shows Macintosh HD is missing (with Recovery HD occupying the entire space)

So yesterday I managed to screw up my iMac 2012 (with Fusion Drive) by installing the Mac OS X 10.10.2 update... The installation stalled and when I tried to restore from an external drive using Time ...
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2answers
791 views

I think I messed up the Fusion Drive on my 1TB iMac (with BootCamp)

this is a somewhat similar post to this one (Can't create partition on free space with Disk Utility) but not quite... It started with me creating a BootCamp partition (around 145 GB) for Windows ...
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1answer
37 views

Free Space Won't Delete [duplicate]

I am running OSX Yosemite. I had free space on my partition, (see picture below) but now it wont delete. I change the format to Mac OS Extended (Journaled), and then when I hit the " + " button it ...
13
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7answers
49k views

Unable to Resize Partitions

I have recently created a partition on my macbook air running OS X 10.9, and this was to run install another OS instance (Yes, OS X 10.10 Yosemite, but that is an aside to the query I have) on it. I ...
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3answers
374 views

Clear free space in Disk Utility

So I recently removed Windows 7 from my iMac, but Bootcamp didn't let me do it. I used Disk Utility instead. The old Windows 7 partition now shows up as free space. I want to reinstall Windows 7 again ...
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0answers
30 views

Change write permissions on internal HD outside of OS

I have a late 2009 iMac with a 1TB internal HD. I am unable to boot the OS however when running disk utility, through target boot and booting into an external HD, I am unable to repair, erase, ...
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2answers
347 views

Unable to shrink a partition in osx 10.10

Hi, I installed windows using bootcamp, but i made the mistake to make the bootcamp only 20gb, so i want to expand it. I found a way to do so, but firstly i need to shrink my other partition - ...
0
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0answers
55 views

USB key/disk not identified as a storage device

I have a 64GB USB key that I suddenly can do nothing with...I've tried both Mac and Windows diagnostics, as described below. At this stage I don't mind losing its data (99% of which was recently ...
3
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3answers
3k views

Yosemite Disk Utility: You may only split this volume in two

I just upgraded to 10.10- Yosemite. I have an external 4TB hard drive. These are the problems I see with Disk Utility: No more than two partitions are allowed. Changing the partition size I can ...
2
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2answers
73 views

Flashing folder at start up, all recommended troubleshooting has failed

I really hope someone might be able to help with this cause I am getting frustrated beyond belief. I have a MacBook Pro with Mavericks OS X 10.9. About a week ago it crashed while I was printing, ...
1
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1answer
105 views

Not possible to create a sparsebundle image on a SMB mounted Volume

I'm trying to create a sparse bundle image from Disk Utility directly on my NAS (through a mounted smb volume): I then get the following error after a few seconds: Creating a sparseimage the ...
2
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2answers
1k views

hdiutil: compact failed – Function not implemented

When compacting a sparse image with the hdiutil compact command, it fails with the message hdiutil: compact failed – Function not implemented.
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1answer
440 views

What does “EFI system partition couldn't be created” mean?

When trying to click "Repair Disk" on an external hard drive from Disk Utility, I got the following error message: ... Repairing the EFI system partition's file system Updating boot support ...
0
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2answers
304 views

Partition issues after deleting Core Storage Logical Volume Group. Everything prompts an unmount error. HELP!

I followed the instructions on this link (last answer) to delete the Core Storage Logical Volume Group via terminal while pressing Cmd+R during startup. These are the functions I used in terminal: ...
2
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4answers
13k views

Restore Macintosh HD to its original partition configuration

I seem to have badly botched a Boot Camp installation of Windows 8.1. I used Boot Camp Assistant to create a 200 GB BOOTCAMP partition on my 1 TB Fusion Drive. I then rebooted and failed to install ...
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1answer
73 views

How do I resize an ex-CoreStorage volume?

I've got a Macbook Pro Retina (with the PCIe drive ‘blade’, instead of a traditional 2.5" laptop drive). I've recently upgraded the internal drive from 500GB to 1TB, and dd'd the old drive over the ...
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1answer
322 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 ...
4
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1answer
801 views

Can't make more than two partitions

I want to multiboot my MacBook Pro, I'm trying to make partitions but in Disk Utility I can't make my partitions, only can divide by 2? Why? It's a normal SSD not a fusion drive (SSD+HD). Now I'm ...
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1answer
1k views

USB pendrive/disk formatting clarification

I have three doubts regarding USB pendrive formatting. Is there is any simple/quick way to format the USB pendrive from MacBook Pro? Now, I am doing this by Applications/Utilities/Disk Utility -> ...
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0answers
15 views

How do I repair an encrypted sparse disk image from the command line?

I have tried: hdiutil repairVolume my.dmg.sparseimage But I get the error: Ownership of the affected disk is required The sparseimage I am trying to repair is owned by me, and I have R/W ...