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

learn more… | top users | synonyms

0
votes
0answers
23 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, ...
0
votes
2answers
212 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
votes
0answers
34 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
votes
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
votes
2answers
53 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
70 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
votes
2answers
891 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.
1
vote
0answers
68 views

200GB of lost space! Difference in file size between finder and disk utility

I have installed yosemite and I am trying to have a backup using time machine. Time machine gives an error that the external drive size is not sufficient. And here begins the adventure... I have an ...
1
vote
1answer
203 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
127 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: ...
1
vote
4answers
10k 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 ...
0
votes
1answer
57 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 ...
1
vote
1answer
211 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 ...
2
votes
1answer
413 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
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 -> ...
0
votes
0answers
10 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 ...
1
vote
5answers
18k 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
20 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 ...
0
votes
0answers
66 views

Error: -69874: Couldn't modify partition map

I would like to format my usb drive. Disk Utility returns 'Couldn't modify partition map' I run cmd + s fsck -fy. It did not work.
8
votes
2answers
33k 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 ...
3
votes
1answer
6k views

How to fix “Error: -5341: MediaKit reports partition (map) too small” after upgrading to a larger hard disk?

I recently bought a new SSD drive, as my stored data amounts outgrew the old one a little bit. After copying all data using dd if=/dev/disk0 of=/dev/disk1, I want to enlarge my system partition, but ...
1
vote
1answer
220 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. ...
1
vote
2answers
180 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 ...
4
votes
1answer
2k 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 ...
0
votes
0answers
59 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
votes
1answer
249 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 ...
0
votes
0answers
133 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
vote
2answers
98 views

how do I “un-partition” my MACINTOSH HD into one big hard drive?

So I was derping around on my computer (it has a 250 gigabyte hard drive) and thought,"hmm I wonder what happens if I partition off 75 gigs of this". believe it or not, it partitioned off 75 gigabytes ...
1
vote
0answers
10 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 ...
0
votes
0answers
48 views

My PCIe SSD crashed during OS reinstall, now will not mount, unmount, repair

While I'm pretty sure I totally broke the partition table, I've been unable to fix it using tools like testdisk and diskwarrior. My machine crashed during installation of 10.8 OSX on a mercury ...
1
vote
3answers
4k 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 ...
0
votes
1answer
219 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
2k 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
92 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
44 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?
3
votes
4answers
11k 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
30 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 ...
2
votes
3answers
15k 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 ...
0
votes
1answer
192 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 ...
9
votes
1answer
10k 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 ...
3
votes
2answers
92 views

How to convert a DVD to ISO?

On Mac OSX 10.9, how do you convert a DVD into an ISO that I can use with players such as VLC. I wish to achieve this without buying a program. Steps I have tried: Downloading Mac app Burn. It ...
0
votes
2answers
52 views

After erasing 200 GB I need to repair it using the Recovery HD

I was cleaning my macbookpro, erasing all unused files i had on it, after that I decided to erase the free space, so i will have all my files organized and cleaned the "used space", after that I ...
1
vote
1answer
308 views

Is Disk Utility's “Repair Disk” a viable TRIM solution for Mac OS X Yosemite?

I'm upgrading a 2010 Macbook with an Intel 730 SSD. Since Trim Enabler is still available but more risk, I'm trying to get by with just Disk Utility. My question was prompted by this hint which ...
0
votes
1answer
49 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
109 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:~ ...
2
votes
2answers
66 views

Why does Finder see volumes which are not under /Volumes?

If I navigate as high as possible in Finder (under 10.10.2, but this did not appear only recently), I see this window, with many volumes which are long unmounted, ejected and erased. But if I tried ...
0
votes
0answers
29 views

Cannot partition Hard Drive in Mavericks Virtual Box

I am trying to re-size the HDD on my Mavericks virtual machine. I already used VBoxManage --resize on the host computer to re-size the .vdi. Now, when I go to partition the HDD to the larger size on ...
1
vote
0answers
33 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 ...
2
votes
1answer
247 views

Problem after erasing the HD of a brand new Mac (OS X Yosemite) with Disk Utility

I cannot reinstall OS X Yosemite now, as there's no hard drive I could see. I had erased the HD with the idea that it will create a new partition but it didn't, so now I can't see a hard disk on ...
0
votes
0answers
73 views

BootcacheControl.playlist not found, MacBook does not boot anymore

Booting a MacBook with Snow Leopard installed will suddenly stop with the message: Unable to open /var/db/BootCache.playlist: 2 No such file or directory Booting in single-user mode, I can see ...