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

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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 ...
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0answers
22 views

Can't find storage after fixing EFI system partition error

I followed How to fix the error: "This disk doesn’t contain an EFI system partition"? In the final step sudo dd if=/dev/disk1s1 of=/dev/disk0s1 I cloned an existing ESP from an internal ...
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0answers
89 views

Disk utility reports wrong partition size

I am running El Capitan and recently deleted a bootcamp partition. However, I have noticed that Disk Utility is giving me erroneous values when it comes to partition size. When I click on the HDD, it ...
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1answer
1k views

OS X can't unmount disk

My 1TB LaCie Rugged THB decided it was a good idea to stop working all of a sudden. If I open it in disk util I sometimes see an actual name of a partition, but most likely it's not the real name. In ...
2
votes
1answer
1k views

Creating a partition in unallocated space

I left some unallocated space on my external HD (around 200 GB) and now I would like to create a partition on it using gpt in terminal since the Disk Utility tool on El Capitan is not even showing the ...
2
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3answers
3k views

How can I resize a partition on OSX 10.10.5

I have a Mac with OS X 10.10.5 on a HD which had 4 partitions. Using Disk Utility I deleted one of the 4, intending to slightly grow the 3rd (containing the OS), leaving space for a new partition to ...
2
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0answers
246 views

Fixing damaged hard drive after OSX update

I recently tried updating my Macbook Pro Retina to OSX El Capitan, however believing this to be a simple routine update, I did not backup my computer. Of course, the update was unsuccessful, somehow ...
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0answers
96 views

Can't format new SSHD?

I just got a new SSHD, but when I tried to put it in my early 2011 13" MBP and format it from a bootable drive, Disk Utility kept giving me the error message: could not mount disk0s2 with name (null) ...
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1answer
60 views

Stuck on 'Preparing to partition disk'

When I add a new partition it gets stuck on 'Preparing to partition disk'. The new partition is in some empty space in the middle of the disk. As a result of the partition not being there, Windows ...
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0answers
257 views

Missing SSD space on MBPr 13, El Capitan

I have the following problem: I had two partitions, one was ~190 GB, and another ~60GB. Then I wanted to delete the second partition and resize the first one. The deletion went well (I suppose), but I ...
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0answers
165 views

Recovery mode Disk Utility can't see new internal hard drive

Lots of similar questions, but no one seems to be having the exact problem I am. Hard drive on my mid-2012 MBP (Mavericks now, but originally Lion) died; I do have backups (including a clone of the ...
2
votes
1answer
283 views

Deleted Macintosh HD. Need to create a new partition/ partition table

I was trying to install El Capitan. I went to erase Macintosh HD in recovery> disk utility as I wanted to do a clean install. It then deleted the Macintosh partition then gave me an error code saying ...
1
vote
1answer
804 views

I removed Boot Camp the hard way, but then I got a Windows error anyway. Should I be concerned?

The short version: I was running Boot Camp on my Retina MacBook Pro, but I decided just recently to ditch it because I never use it and I'd like to reclaim the space. The official method of removing ...
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0answers
152 views

how to resolve disk partition issue in OSX 10.10.5?

Using Boot camp assistant I have created a partition and installed Windows 7 OS to work on both Mac as well as windows (Dual boot). But later on deleted the windows OS partition(Could not remember how ...
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0answers
55 views

How do merge the free space to my Macintosh HD partition?

I have approx. 370 GB of free space from which I want to merge 200 GB to my Macintosh HD disk. Can anyone please help me on this? I am not even getting the resize option there. System version: ...
0
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2answers
693 views

How to Erase External USB Drive Which Won't Mount & Isn't Recognized

Before starting, let me mention that I have ALREADY read the following thread in its entirety, and it did not help my situation: https://discussions.apple.com/thread/4832305?start=0&tstart=0 I ...
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vote
1answer
812 views

Is it unusual for “Verify Disk” on Disk Utilities to take so long on a Time Machine drive?

I have an external 3TB FW800 drive set up to be my Time Machine drive. I noticed some unusually high drive activity, and opened up Time Machine to see if it was backing up. Nope, TM showed previous ...
1
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1answer
32 views

Can I use the Recovery Partition on one startup disk to repair another (internal) disk?

I have an SSD and an HDD in my Macbook Pro (Yosemite) and I recently cloned the HDD to the (new) SSD. The SSD is now unhealthy, for reasons unknown and Disk Utility recommends repair from the ...
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0answers
18 views

Use diskutil without firmware password

Diskutil found some problems on my drive that need to be fixed in recovery mode. However the it department installed a password in the firmware. Is there anyway to start diskutil without the ...
0
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0answers
7 views

How can I re-allocate the whole space for just one partition? [duplicate]

I'm running OX X 10.10.5 on my MBP with 500GB SSD. When I initially configured the computer I've created a setup with a boot loader so I was able to boot into Linux too. Since I'm using virtual ...
0
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0answers
164 views

How do I change the password on a Time Machine backup image?

I've tried using Disk Utility, but after entering the current password, I get a small dialog reading Unable to change password for “$image.” (Inappropriate ioctl for device). I've also tried hdiutil ...
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0answers
122 views

OS X - USB key Fat32 cannot be open device in Disk utility -

am trying to reformat a brand new USB key ( EMTEC Click2.0 16GB Flash Drive) which is FAT32 formatted ( default) as I need to store oversized files ( > 4GB) to OS X Extended Journaled The key is ...
1
vote
1answer
762 views

How to create a new partition for OS X, then remove the original one

I want to clean install a new version of OS X, so I was thinking to create a separate partition, transfer all applications and settings from my old system and then remove the old partition and make a ...
1
vote
1answer
123 views

Time machine backup or File Vault encryption of encrypted disk image

I have a small encrypted disk image on my Mac (Yosemite), containing account numbers, tax reports and such. I created it using Disk Utility, from folder, which I subsequently safely deleted. I am also ...
0
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0answers
48 views

Bootcamp problems have left my hard drive a mess

I have been trying to install Windows 8.1 via Bootcamp, and have had several problems that have resulted in failures (those are perhaps a different post). I'm using Yosemite. Currently when I run ...
0
votes
2answers
250 views

Resizing HFS+ volume after cloning

I cloned a disk containing an HFS+ volume to a larger disk using the command line dd utility. Now I want to grow the HFS+ volume to fill the new disk. There's an EFI partition before the HFS+ volume ...
2
votes
1answer
131 views

Can't delete empty partition

I've searched around on here and viewed posts such as: I deleted my Bootcamp partition but can't resize my OS X partition Can't ever remove partition? The second one looked most promising, ...
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0answers
1k views

How do I fix “Your Disk Could Not Be Partitioned” isssue with BootCamp Assistant?

I'm Alex and I'm attempting to install Windows 10 on my iMac 27" (2012) with 3TB+128GB Fusion Drive, but during install procedure I get the same error "Your Disk Could Not Be Partitioned" without any ...
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1answer
334 views

Resize Mac Partition is Disabled - how to partition properly

I have two partitions on my mac book pro. One partition is running os Yosemite and other one is running bootcamp windows 8.1. Yosemite is 75GB and Bootcamp has 673GB. I shrinked the windows partition ...
0
votes
1answer
186 views

How to fix my partition table after messing it up trying to install Linux Mint

I tried to install Linux Mint alongside my working OS X Yosemite. I have a Macbook Air released mid 2013 with a 128gb SSD and 4gb of memory. Well to achieve my aim I first added a partition using ...
0
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2answers
309 views

Unable to repair hard drive - due to volume assignment problem?

Disk utility and fsck [terminal] both agree that there is problem with my HD. I am curious if someone can help me figure out how I can deal with the problem. Terminal - Normal Mode MacBook-Pro:~ ...
1
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1answer
1k views

External hard disk not showing up on finder and can't be verified in Disk Utility

My Mac suddendly restarted and now the external hard disk I normally use for Time Machine backups is not working anymore. When I plug it in, it doesn't appear on finder and while it appears in the ...
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0answers
37 views

RAID + FileVault and startup partition

From this answer: Why doesn't FileVault work on a RAID volume? I learnt that it is possible to have RAID and FileVault together. However it seem that the solution is for a separate data volume not ...
1
vote
1answer
248 views

Disk Utility reading disk incorrectly; viewing ext4 as JHFS+ and seeing Recovery HD

This is imported from Superuser, I felt like I would have an easier time getting an answer here than in Superuser - it is copy pasted, as below. So, I have some strange issues in Disk Utility and ...
0
votes
1answer
1k views

“Unable to unmount volume for repair” message from reformatted SSD in “Option/ALT startup” using bootable USB

I am trying to reformat a Samsung 512GB Pro with bootable USB, and I have manage to get through the prep for the USB. But after the "Option/ALT startup" i click on the USB to begin with and when the ...
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0answers
167 views

BootCampAssistant “Install or delete Windows 7” greyed out

I need to install a Windows 7 on my MacBookPro but the installation button is actually greyed out. I first managed to install a first windows but i needed it to be bigger, so i deleted the BootCamp ...
0
votes
1answer
53 views

Cannot Partition Disk with Disk Utility

I can't seem to partition my disk with Disk Utility or with the Terminal command (see screenshots). Something also happened to my other partition running Mavericks, where it just turned into an "empty ...
4
votes
1answer
1k views

how to fix GUID hard drive corrupted to MBR

I am on OS X 10.9.5 with a late 2013 iMac. I have a 3TB hard drive that has an unusual problem. It is a Western Digital 3TB Red WD30EFRX. I formatted it with two partitions, both 1.5TB. One was a ...
0
votes
1answer
183 views

Why can I only have 2 partitions on my 3TB Apple Fusion Drive?

According to Apple, I can only have 2 partitions on my 3 TB Fusion Drive. I do not understand why. Techtool Pro made an eDrive, their emergency boot drive, and Apple made their Recovery HD. It ...
1
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1answer
20 views

I cannot do bootcamp but my hard disk only have machintos HD and Data

The bootcamp said that my disk cannot be partitioned or restored as single partition. I am using macbook pro 15" but idk the version but the graphic card said gt320m 256 MB and 350 GB HDD i5 do i ...
0
votes
1answer
143 views

recover partial backup data from a (potentially damaged) Time Machine disk

I am on a MacBook Pro Retina 15-inch, late 2013, with OS X 10.9.5 Mavericks. First of all, to clarify the question, my goal is to create a new, working Time Machine (TM) disk, that has as much as ...
0
votes
2answers
399 views

Backup disk suddenly won't work

Here's the error message I get: "An error occurred while copying files. The problem may be temporary. If the problem persists, use Disk Utility to repair your backup disk." When I try to follow that ...
0
votes
1answer
127 views

Can't edit partitions with Disk Utility in OS X 10.10

I'm having trouble accessing about 50GB of space on my computer after a failed partitioning attempt. Before you ask, I don't know what went wrong, I just know that now, I can only turn the free space ...
1
vote
1answer
59 views

How to backup and restore MBP hard drive before reinstalling OS X?

My MBP Retina 13″ late 2012 is showing the stop sign and I know that I need to reinstall my OS. I have not got my hard drive backed up with Time Machine. Is there a way in which I can backup my hard ...
0
votes
1answer
57 views

Disk Utility not letting me Partition Disk

A bit of background before I start. I'm trying to install Ubuntu onto my Macbook Pro and so far I've stumbled into a bit of a roadblock. I've also already installed Windows 10 with Bootcamp, I'm not ...
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votes
2answers
2k views

Can't restore Time Machine backup to Macintosh HD

Today I found my Mac shut down. It won't boot again anymore. When I try to turn it on, it just shows the Apple logo, a loading bar and after 1/3 progress it just shuts down again. After some research ...
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0answers
51 views

How to monitor progress of disk decryption in recovery mode

As the title states, I am decrypting an external drive using Disk Utility in Recovery mode, and would like a way to know the progress or completion as well as any errors. Is there a known way to do ...
2
votes
1answer
91 views

White prohibitory sign on Startup

Have the white prohibitory sign when trying to boot up MBP Retin 13" late 2012 running Yosemite. Have tried resetting PRAM (cmd + alt + p + r) and disk utility has been to no avail so far. Have tried ...
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0answers
82 views

Mounted image appears empty in Finder

I decided to reinstall MacOS X from scratch. I have rebooted my mac with Cmd+R, then used Disk Utility to create a .dmg disk image on a USB drive. I then rebooted the computer and verified that I ...
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2answers
945 views

Why can't I boot to Disk Utility (iMac A1418) - It displays a lock and a password field?

Someone showed me their iMac that they recently bought second-hand. It boots normally to the login screen with the PIN (EDIT: it is a PIN and NOT a passcode; the message reads "Enter your system lock ...