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

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3answers
48k 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 ...
1
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0answers
3k 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 ...
0
votes
1answer
2k 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 ...
3
votes
4answers
2k 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 ...
0
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2answers
69 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. ...
0
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1answer
152 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 ...
2
votes
1answer
10k 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 ...
1
vote
1answer
80 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 ...
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3answers
1k 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 ...
3
votes
3answers
5k 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
votes
2answers
2k 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
vote
1answer
901 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 ...
1
vote
1answer
4k 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
votes
2answers
8k 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: ...
6
votes
4answers
59k 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 ...
4
votes
1answer
10k 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 ...
0
votes
1answer
2k 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 -> ...
2
votes
5answers
30k views

How do I fix my SSD after installing Yosemite and Enabling TRIM? No boot & can't erase

I recently upgraded to Yosemite, enabled FileVault and foolishly enabled TRIM (had no idea it wasn't supported). Upon restart, my machine gets the grey screen with the crossed-out circle of death. ...
0
votes
1answer
49 views

disk become empty after delete a large file

I have a 2T mobile disk with the format of NTFS. I store 1T files on it, including a large file with the size of 260G. After I delete the large file, all the file was gone. I remount the disk again ...
1
vote
1answer
332 views

How can I reconfigure the RAID settings on a Maxtor OneTouch III?

I have a 1TB Maxtor OneTouch III. This is the drive that comes with two 500GB disks and software to configure RAID 0 (mirroring) with 500GB of storage, or full use of both disks for 1TB of storage. ...
4
votes
1answer
9k views

OS X Yosemite Hard Disk Errors even after Repairing them

Basically, I do a lot of C programming (for class) so I use gcc a lot on my mac. Recently since two days, whenever I ran it, the entire computer is getting frozen, and a force restart is necessary to ...
1
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0answers
393 views

Why does hdiutil fail on symlinks when creaing an image of a Time Machine backup?

I am trying to create a compressed disk image of a Time Machine backup (that is stored on an external HDD) on Yosemite. hdiutil fails on the first symlink it comes across. Before the failure, there ...
0
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0answers
782 views

WD My Book Media shows up in diskutil, but doesn't mount or show up in Disk Utility

Initially this drive was connected (via FireWire) to my wife's Mac (still running OS X 10.7), but she it would not mount any more and she asked me to look at it. After reading suggestions on-line, I ...
1
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0answers
44 views

Partition failed performing a fresh installation

I'm trying to partition a samsung ssd and want to perform a fresh OS X snow leopard install from dvd. When I try to partition the disk in diskutil I get: Partition failed POSIX reports: The ...
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vote
3answers
6k views

How do I restore a Windows 7 DMG file to Boot Camp (and make it bootable)?

My iMac's HD died last week, and so I was unable to access OS X (I had a Time Machine backup of it though). Fortunately I was able to boot into the Recovery HD and use Disk Utility to backup Boot Camp ...
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vote
1answer
3k views

How Do I Partition A Raid 0 Using Disk Utility?

I have just purchased a WD My Passport Pro. It comes in a striped RAID 0 configuration comprising of two 2TB drives. I want to partition the drive into 3: Photoshop Cache Lightroom Catalogue Video ...
3
votes
4answers
3k views

“Not enough space” on partitioning?

I have a 320GB harddrive with 95GB free. I boot to a 10.5 disk, open disk utility, and add a 40GB partition. Halfway through the progress bar, though, it tells me that there's not enough space. I'm ...
1
vote
2answers
243 views

Why can't I delete the second partition

So I was playing around with Disk Utility today. I created a second partition. Format is Free Space. How do I undo this? As in, I want to have just one primary partition "Macintosh HD" I've tried: ...
1
vote
1answer
582 views

How to locate “other” files on an Imac [duplicate]

When I look at my available disk space on my imac it says ive used 700 gigs for "other" files. How do i find these files and delete them?
4
votes
4answers
21k views

Recovering data off of a dead hard drive

My hard drive died in my macbook and it no longer will start up. It will not mount in an external enclosure but disk utility is still reading that the hard drive is there, and I tried to repair disk ...
1
vote
1answer
214 views

Mounting a RAM disk on startup, but seems to be unmounted automatically

I wrote a simple script that mounts a ram disk: %> cat /System/Library/LaunchDaemons/ramdisk.plist <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//...
12
votes
1answer
15k views

Can't ever remove partition?

Running Mountain Lion. I added a partition with Disk Utility and then had second thoughts about it. I'd like to remove the partition i created, MacSSD2 and hand over its space back to MacSSD. As you ...
0
votes
1answer
128 views

How can I format a USB stick that's falsely marked as read-only?

I was trying to create a bootable disk with Windows on it through bootcamp, but something went wrong during the installation. Now I have a read-only USB stick with corrupt files I'd like to fix. My ...
0
votes
0answers
978 views

Can't add more than 2 partitions

I'm trying to create more than 2 partitions on my mac book pro retina 2014, 256ssd but disk utility only permit me to add one partition. Last login: Tue Dec 30 17:24:32 on console Joses-MacBook-Pro:~ ...
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vote
0answers
77 views

WD Drive Cannot be Repaired but program still running

I have an external hard drive that I use to run my iTunes, iPhoto library and store various other documents. Recently, it stopped connecting to my MacBook Pro. I can only see my WD Ultra external ...
3
votes
2answers
2k views

Format External Disk in FAT, NOT FAT32

I have an external device which mounts as an external drive and which I must format in FAT, not FAT32, for use elsewhere. Is there a way to do that from Snow Leopard?
0
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0answers
1k views

Drive name red in Disk Utility: Core Storage Drive offline. How to bring back?

Yesterday, my mac wouldn't boot up. When I restarted, I could get the whole way to the User login screen. No matter what user I chose, the boot bar would get about 1/3 way finished and I would get ...
2
votes
1answer
9k views

MacPro Hard Drive 3 TB or Larger formatted to Logical Volume Group by Disk Utility

I have an Intel MacPro in which I recently installed a new internal 3TB hard disk. I attempted to format it in Disk Utility using the standard GUID partition map and encountered a strange problem. ...
0
votes
1answer
195 views

Restore a lost partition from degraded software mirror RAID

I used to store my valuable files on Apple software RAID (mirror). Recently one disk has failed and the mirror became degraded. I rebuilt the mirror using new drive, following this guide, but seems ...
2
votes
0answers
3k views

Disk Utility: Invalid Disk Label @ cksum mismatch

I have a WD external hard drive. I've been running the routine tests to make sure all my stuff is safe lately. In Disk Utility, I did Verify Disk on both the disk itself as well as the main partition, ...
3
votes
1answer
197 views

Interesting partition Map with missing HD space

I have the latest generation Macbook Pro running Yosemite, I bought this computer used I don't know if the last person attempted to install linux or what the story is but I believe my partition map is ...
0
votes
1answer
602 views

Can not reinstall Windows7 (using Boot camp) after i've removed Bootcamp partition via Disk Utility

I've removed Windows partition (might be label as Bootcamp) using Disk Utility. and after that i found that i made some mistake because in actually i should remove it via Bootcamp Assistant. What's ...
0
votes
1answer
847 views

OSX Yosemite can't resize partitions?

A few weeks ago I installed OS X yosemite.I did it on the standard partition, but I had a dual-boot with ubuntu. I realised that the ubuntu boot was gone so I tried to redo it. But in disk utility, ...
0
votes
1answer
3k views

Macbook Lion Recovery Disk Utilities cannot detect newly installed SSD

I just installed the SSD and I cannot detect the SSD in Disk Utilities of the recovery disk. Even trying to restore from time machine backup it cannot find any disk it can restore to. I am restoring ...
0
votes
1answer
4k views

Yosemite freeze at boot - no safe boot + I/O error

Yesterday everything was fine but today my macbook freeze/stuck during the boot. I've done this: check + repair permission (nothing changed) check + repair disk (nothing changed) tried safemode ...
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vote
0answers
47 views

Can't unmount Macintosh hd with Mavericks with lion bootable USB

Hi I'm trying to revert back to lion after using the sixty four on thirty two method to install Mavericks on a mac pro 1,1 but for some reason when I boot from a USb with the lion installer I can't ...
0
votes
1answer
486 views

“This is a startup partition. You can't erase it” On Disk Utility

I want to expand my Windows partition. I saw all the tutorials on youtube and they said to drag the drive on the corner. However, the Disk partitions doesn't have a drive for me to drag and said that ...
1
vote
1answer
2k views

Can't mount (Core Storage) encrypted volume anymore

I use the following setup: SSD: System Internal HDD: Data (Documents, Music, etc.) Both disks are encrypted via the Core Storage utility. It seems I can't mount the "Data" disk anymore. I wanted ...
0
votes
1answer
4k views

"You can't resize the partition on this disk because it uses the Master Boot Record partition scheme [duplicate]

I am trying to get rid of one of the volume ("mountain Lion", the second from the top) of the partition of an external hard-drive. In disk utility I get what you can see in the pic, namely it does not ...
1
vote
3answers
327 views

Partition problem after HDD to SSD swap

Recently decided to replace my nearly full 500GB HDD with a 1TB SSD to breathe some new life into my mid-2010 Macbook Pro. I used a toaster-style drive cloner (Dyconn Dubbler) to do a sector by sector ...