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

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2answers
57 views

Missing disk space after repartitioning

I tried to make a partition and then tried to undo it. Now, I don't know how to get the missing disk space back. As you can tell, I have 751.28 GB disk. Macintosh HD and Recovery HD have 557.4 GB. ...
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1answer
86 views

Can't delete/merge my partitions on OSX

Yesterday I tried to install Win10 through bootcamp, but it couldn't install it on the premade partition. Eager as I was i meddled with the partition scheme during the installer but with no result. ...
1
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1answer
17 views

Confused about Compressed option in Disk Utility?

When I use Disk Utility to create an image, it gives me five options: Read only Compressed Read/Write DVD/CD Master Hybrid Image Most of these make sense to me why someone would prefer one option ...
25
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6answers
37k views

Resizing or expanding a CoreStorage volume

I bought a new SSD with 750 GB and made two partitions: 600 GB and 150 GB. The smaller one was thought to be a Bootcamp partition one day, but to date it was just another unused partition. When I ...
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1answer
38 views

Moving Recovery HD partition to end of disk

This is my current partition map: $ diskutil list /dev/disk0 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme ...
11
votes
10answers
66k views

Macbook HD “Other” all the Sudden Almost Full

As you can see in the below image, my HD "Other" category is almost full. A couple of days ago, I randomly kept getting a popup saying that my disk was almost full. Then I went in and noticed the ...
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1answer
55 views

Unable to erase, reformat, or repartition USB drive

This afternoon I attempted to mount a .iso of Windows 7 to a bootable USB drive. It's about 370GiB, so more than enough to store it. I did the following to get myself into this mess. Note,/sda/disk2 ...
6
votes
4answers
597 views

How to mount disk by UUID or LABEL in OS X El Capitan?

I get the UUID and label of a disk from diskutil info disk0s4 diskutil info disk0s4 Device Identifier: disk0s4 Device Node: /dev/disk0s4 Whole: No ...
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1answer
75 views

First Aid Fails on External Disk, what can I do from here?

History: Running an iMac late 2011 and updated the OS to Yosemite when the computer stopped booting. I have a history of killing HDD so I figured it was a bad HDD and I went to change the drive. ...
13
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4answers
45k views

“Warning: SUID file has been modified and will not be repaired” after repairing disk permissions

Warning: SUID file “System/Library/CoreServices/RemoteManagement/ARDAgent.app/Contents/MacOS/ARDAgent” has been modified and will not be repaired. I keep getting this after running Disk Utility to ...
1
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1answer
24 views

Repairing permissions twice gives the same result

If I repair permissions twice in a row, without launching any apps or processes while I do this, the results are almost the same: Why is it that the second time around, the problems seem to be ...
0
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1answer
44 views

Partition alert message when using Boot Camp Assistant: “The startup disk cannot be partitioned or restored to a single partition.”

I have a 13" Early-2015 MBP Retina in which I am trying to install Windows 8.1 on. When I went into bootcamp, I received the ever so common error of: When I went to the newly designed disk utility, ...
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1answer
251 views

Flashing folder icon appeared once after changing Macbook hard drive

About 2 weeks ago, I updated my late 2011 Macbook Pro hard drive to a Crucial MX100 solid state drive. The drive installation and data migration went fine with no issues, but today I found the ...
2
votes
3answers
5k views

Restore Recovery HD partition from Yosemite downgrade

I recently got back to Mavericks from Yosemite, everything went fine. As I normally do, I checked my HDD with the Disk Utility and found some trouble, then I boot on recovery mode to fix my HDD. I ...
1
vote
1answer
86 views

Partition type suddenly FFFFFFFF-FFFF-FFFF-FFFF-FFFFFFFFFFFF, drive unmountable

I have two drives inside my MBP, an SSD for the OS and the original HDD for large Data. The HDD has 3 Partitions: My Data (Core Storage volume) 20Gb for Linux 4Gb for Linux Swap Recently I ran ...
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1answer
42 views

How do I increase the size of the main partition?

As indicated in the screenshot I can't increase the size of the main partition.
0
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1answer
46 views

Missing disk space after failed Bootcamp install

Earlier today, while running Bootcamp attempting to install Windows 7 on my late-2012 iMac, I suddenly lost 160g of disk space after Bootcamp failed to create the partition for Windows. Disk Utility ...
3
votes
4answers
3k 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
1k views

How to make Macintosh HD size the same as SSD

So today, I tried dual-booting my late 2013 rMBP on El Capitan with Windows 10. I got to the step within Bootcamp where it was partitioning my SSD, and I went ahead and played a game of Super Smash. ...
8
votes
3answers
12k views

How can I mount an encrypted disk from the command line?

When I type diskutil mount disk3 in the terminal, it says Volume(s) mounted successfully. However, the disk is not mounted and I can confirm this by opening the GUI of Disk Utility.app and also the ...
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vote
2answers
43 views

How to exercise a new hard drive by erasing multiple times with Disk Utility app?

In El Capitan, in the Disk Utility app, I cannot find the option to rewrite bogus data (zeros or ones) across the entire drive multiple times. I am using a spinning rust platter disk, not an SSD. ...
0
votes
1answer
14 views

Macbook pro internal HD not detected

I had a problem with my bootcamped MBP and I tried to format the HD. I wasn't able to format any of the partitions so I tried the following based on https://www.macissues.com/2014/04/05/how-to-fix-...
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1answer
2k 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 ...
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0answers
17 views

Disk Utilities verifies disk with no repairs needed, but Mount says disk must be repaired

I was transferring some files off an old FireWire drive yesterday, but when I turn on the drive today it doesn't automount. I go to Disk Utility and see the drive, try to mount it, and get this ...
0
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1answer
26 views

Adding partition to disk creates unwanted third partition

I'm using disk utility to try to divide the partition I'm working on, which is 51.28 GB, into one main partition (to run OS X on) and one smaller HFS+ partition (on which I will eventually install ...
0
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1answer
91 views

Merge Partitions with Disk Utility in El Capitan Gives operation Failed error

I accidentally created a partition of 1.05GB space. Went to Disk Utility -> Partition, and I clicked on the - sign to remove it and hit "apply". It gives me the following error: I have another ...
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2answers
4k views

Has El Capitan Disk Utility Removed Encryption Options?

With Mavericks I would unlock an encrypted disk using "Disk Utility", but in El Capitan the "Unlock" button isn't there.
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2answers
48 views

Error restoring encrypted disk using Disk Utility

I am trying to replace the hard drive in an old MBP-15 mid 2010 with a new SSD. The old disk is encrypted. I did that on my own two MBPs successfully, but both disks were not encrypted. The Mac is ...
2
votes
2answers
187 views

Disk Utility (recovery mode) stuck at loading

I want to do a clean install of el capitan OS. I booted to recovery mode, chose reinstall os x and followed the steps. So far so good. When it came to choose the destination disk where I wanted to ...
0
votes
1answer
50 views

I need to make my partitions into a single one after a failed bootcamp, how do i do this?

I am a complete novice when it comes to macs. I recently tried to use bootcamp to run windows 10 and partition part of my hard drive. I used the bootcamp assistant and I followed all of the steps but ...
0
votes
0answers
12 views

Cannot delete a disk partition OSX El Capitan 10.11.4 [duplicate]

For some reasons that is the only partition I can't delete but it's empty... I don't even remember ever creating it in the first place. As you can see both + and - are deactivated. Is there a way of ...
1
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1answer
92 views

OS volume shows as type 'FFFFFFFF-FFFF-FFFF-FFFFFFFF' after attempting to delete some Linux partitions—cannot log in

I was unable to just delete the partitions left by an old Linux Mint installation by pressing the '-' button in disk utility. I looked online and read that I could reformat them to a journaled format ...
0
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1answer
90 views

Missing Space on Drive using Core Storage after Boot Camp Assistant Failure

Using Boot Camp Assistant, I started to create a 50 GB partition, but it hung on partitioning. After waiting about 30 minutes without the progress bar moving, I quit the Boot Camp Assistant, thinking ...
0
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0answers
31 views

How can I add a partition to my Seagate external hard drive?

I am trying to add a partition to my Seagate external hard drive so that I can install Windows 10 on it but it won't let me add a partition at all. With a previous external hard drive I had (that no ...
3
votes
2answers
893 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 ...
2
votes
2answers
259 views

My SSD Drive has been converted to a Core Storage drive and cannot be erased/reformatted?

I put an SSD drive into my macbook pro. I should say that this drive hadn't been formatted and was a bootable drive with Yosemite OS on it, taken from another macbook pro... I booted the system up in ...
0
votes
0answers
138 views

After stuck “Partitioning disk” by Boot Camp

I use a MacBook Pro Late 2011 with OS X El Capitan (10.11.4). I wanted to install Windows using Boot Camp Assistant. However, I got stuck at Partitioning disk.... It seems that it is a very common ...
0
votes
0answers
20 views

Lost disk space after partitioning w/ disk utility crashed

I made the mistake of deleting a bootcamp partition thru disk utility in hopes of making a larger partition with a fresh windows install. As I tried making a new FAT partition in disk utility I ended ...
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2answers
123 views

Windows failed to start after upgrade to El Capitan

There is something very frustrating I am trying to figure out for a few days. My MacBook Pro has a 500 GB hard drive. It had Mac OS 10.6.8. There was a Windows7 installation done some time ago via ...
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0answers
28 views

El Captan disk utility did not see erased partition after fail bootcamp install

I try to get my full drive after fail a bootcamp install of Win. Now I have removed extra partition from my fusion drive, but can’t see empty space using the el captan disk utility. Using shell, ...
0
votes
1answer
76 views

How to install a bootable ISO onto a single partition of a usb stick?

Previous questions/answers dealt with the simple case of a single partition on the USB disk that was just overwritten with dd. Also it looks like the disk utility gui doesn't allow creation of ...
0
votes
1answer
96 views

Messed up my 1TB Fusion drive on my iMac with Disk Utility

Soooo something bad happened recently with my 1 TB Fusion drive on my 5K late 2015 iMac. I was creating a new 100 GB partition on my disk. So while the disk utility was busy scanning etc (doing its ...
0
votes
0answers
17 views

macbook ssd hard partition unmount

Yesterday my fiend used my macbook to set his flash memory bootable but he made mistake and select my mac disk volume instead of his flash! Now when I restart macbook it shows a slasher question ...
28
votes
9answers
120k 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 ...
5
votes
3answers
19k views

How do I force a partition and format on a USB key in OS X Mountain Lion Disk Utility or from CLI diskutil?

I have a brand new Memorex TravelDrive 64GB USB disk which is being troublesome. It's formatted FAT16 on MBR, which is not so nice, and I'd like to put it on HFS+. I've tried to do this through ...
5
votes
4answers
15k 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 ...
1
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0answers
38 views

My partition is using negative space. Should I worry?

As you can see, according to Disk Utility, I'm using negative space in /dev/disk0s7. This is obviously incorrect, however, I am slightly worried as to what this may mean for the partition's effects on ...
10
votes
5answers
69k views

Unable to format / erase hard drive

I have an external HD that died on me a while ago and I'm trying to see if I can format / erase it to start using it again. The disk does not show up in Finder but I can see it in Disk Utility. When ...
1
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1answer
61 views

No Macintosh HD in Volumes folder

I am running in recovery mode to save the data from disk( I cant login due to deletion of private/var folder). I opened Terminal and went to Volumes. This folder should be populated with the Macintosh ...
1
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1answer
36 views

Unidentified hard disk space getting in OS X apps section

Last night I got an issue with my MacBook Pro. After updating the OS to El Captain it shows the 50+ GB storage space for the Apps section. But after a couple of hours it shows 160 GB space. It's ...