Disk Erase Error Cannot Unmount Disk
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Disk Erase Failed With The Error Couldn't Unmount Disk
tip: Fix 'couldn’t unmount disk' errors 7th May 2014Russell Harris11 CommentsBlog I have found myself recently experiencing a couple of Macs which would not allow me to repair the directory or permissions
Disk Erase Failed With The Error Couldn't Unmount Disk External
in Disk Utility, or erase/partition the drive with an error such as: ‘Disc erase failed couldn't unmount disc' or ‘Disk Erase failed with the error: Couldn’t unmount disk.' Even trying to use Network Deployment tools such as Apple's Netinstall service or DeployStudio have also failed to deploy due to these errors. Normally, any ‘Couldn’t Unmount Disk' error is attributed to circumstances where the boot drive is secure disk erase failed with the error couldn't unmount disk being modified or is being used by an application or process. So the first thing to do is to startup the Mac from another bootable drive such as an external drive or OS X Recovery. You can then run Disk Utility from there. An external drive or a network drive is preferred if it is the internal hard drive you have an issue with, since the OS X Recovery is a partition on the same physical drive which may not be able to successfully unmount or modify your internal disk. To create your own bootable disk, refer to our blog ‘Creating a Mavericks bootable install disk'. I would strongly recommend at this stage attempting to back up any data that is required before proceeding with the following steps. Some of the following steps are destructive and will lose ALL data on your drive. If you have an external bootable disk, connect this to your Mac and power your Mac up whilst holding down the OPTION/ALT key. Then select the desired external drive from the startup manager screen and press the enter key. If you have used our method above to create a bootable installer, choose ‘Di
a title. You can not post a blank message. Please type your message and try again. studio_ Level 1 (2 points) Q: Disk Erase failed with the error: Couldn't unmount disk. Running
Disk Erase Failed Could Not Unmount
Mavericks I am running Mavericks OX 10.9.1 and am trying to erase an disk erase failed couldn't unmount disk usb external hard drive that has been partioned. I keep coming up with the error message "Disk Erase failed with disk erase failed couldn't unmount disk mavericks the error: Couldn't unmount disk." Any suggestions? iMac, OS X Mavericks (10.9.1) Posted on Jan 21, 2014 1:45 PM I have this question too Close Q: Disk Erase failed with the error: http://www.amsys.co.uk/2014/05/disk-utility-tip-fix-couldnt-unmount-disk-errors/ Couldn't unmount disk. Running Mavericks All replies Helpful answers Page 1 of 4 last Next by Kappy, Kappy Jan 21, 2014 1:48 PM in response to studio_ Level 10 (271,467 points) Desktops Jan 21, 2014 1:48 PM in response to studio_ Eject the drive, wait a minute or two, then reconnect it. Try again. Helpful (3) Reply options Link to this post by studio_, studio_ https://discussions.apple.com/thread/5812340?tstart=0 Jan 21, 2014 2:11 PM in response to Kappy Level 1 (2 points) Jan 21, 2014 2:11 PM in response to Kappy Hey Kappy, thanks for your reply! It was a no go though Helpful (0) Reply options Link to this post by Kappy, Kappy Jan 21, 2014 2:17 PM in response to studio_ Level 10 (271,467 points) Desktops Jan 21, 2014 2:17 PM in response to studio_ There must be something on the drive that has a connection to the internal drive, I think. Try booting from the Recovery HD:Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the arrow button below the icon.Select Disk Utility from the list and click on the Continue button. See if this lets you erase the drive. Helpful (1) Reply options Link to this post by Dr.Mac., Dr.Mac. Jan 21, 2014 2:26 PM in response to studio_ L
to Disk erase failed. Couldn't unmount disk, then you may have to force an unmount through the terminal. Launch up Terminal.app (through /Applications/Utilities http://technology.siprep.org/fix-for-disk-erase-failed-couldnt-unmount-disk/ or through a Spotlight search). Then paste in the command: diskutil list to http://apple.stackexchange.com/questions/184864/mac-mini-cant-unmount-disk-in-recovery-mode list out the different disks. You should see some disks appear like /dev/disk0, /dev/disk1, /dev/disk2. Find the one you want to force unmount. For this example, let's say it's /dev/disk2. Run a command similar to this one sudo diskutil unmountDisk force /dev/disk2 If you're prompted for a password, enter it (yes, your disk erase account does need to have administrative privileges). You should not physically unplug the drive. You should now be able to erase the drive. Author Alan SiuPosted on April 13, 2015Tags disk utility, diskutil, erase drive, mac, unmount 30 thoughts on “Fix for disk erase failed couldn't unmount disk” Randall says: July 14, 2015 at 9:12 am This worked perfectly for me! After searching for a very disk erase failed long time through forums of people suggesting basic things or trying to make others feel ignorant this solution worked! Thank you so much. I now have a useable disk where before it would not mount and could not be formatted or erased. Running OS X 10.9.5. I will be linking this solution to other forums in the future. http://technology.siprep.org/fix-for-disk-erase-failed-couldnt-unmount-disk/ Reply Bobby says: October 9, 2015 at 5:17 pm Excellent post! It worked the 1st time for me, and i also had to stumble across the interweb minefield before finding this solution. Thank you ! -Bobby Reply Lissett says: October 11, 2015 at 10:19 am Worked for me as well! Thank you so much 🙂 Very clear instructions! Reply Jason says: November 5, 2015 at 8:50 am I tried this method, but now it says "Forced unmount of disk2 failed: at least one volume could not be unmounted" Please help, I would like to erase my hard drive so i can do a clean install of el Capitan Reply Alan Siu says: November 5, 2015 at 9:04 am Odd. I've never seen that. I did Google your error, and came across this workaround. Give it a sho
Start here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more about hiring developers or posting ads with us Ask Different Questions Tags Users Badges Unanswered Ask Question _ Ask Different is a question and answer site for power users of Apple hardware and software. Join them; it only takes a minute: Sign up Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top Mac Mini can't unmount disk in Recovery Mode up vote 0 down vote favorite I need to wipe my Mac Mini and reinstall OS X. Booting into recovery mode (holding command+option+R), I try to erase the disk in Disk Utility but it says it cannot unmount the disk or gets stuck on "Unmounting disk" with an infinite loading progress bar. I have also tried booting into the recovery partition by holding down option at launch, but the same applies. hard-drive boot disk-utility recovery share|improve this question asked May 5 '15 at 17:19 Chris 11817 There must be something active on it that does not let it unmount. Did you try using Terminal ? –Buscar웃 May 5 '15 at 18:06 I tried unmounting via terminal but the only thing that shows up under /Volumes/ is the base partition :( –Chris May 5 '15 at 19:28 Try resetting you PRAM/NVRAM. See Cannot Unmount Mac OS X Base System Disk. –David Anderson May 6 '15 at 11:03 add a comment| 2 Answers 2 active oldest votes up vote 1 down vote Way by Terminal.. Use diskutil list in a Terminal instance to list all volumes and find yours. Then do hdiutil eject disk? Replace the ? with your disk number, making sure you are not trying to eject the main hard drive :) It is probably called "Disk1" Here is a Sample when I insert a USB stick and run diskutil list disk0 is my hard drive and I can NOT eject that one disk1 is the USB and I cam eject it. share|improve this answer edited May 5 '15 at 20:27 answered May 5 '15 at 18:09 Buscar웃 24.9k42576 hdiutil: couldn't unmount "disk0" - Resource busy –Chris May 5 '15 at 19:31 There you go, now we know it is busy with something :) Warning, make sure you are unmounting the right disk, as shown in the diskutil list. –Buscar웃 May 5 '15 at 19:34 How do I unbusy it? I just want a fresh install, no need to have any data recovered –Chris May 5 '15 at 19:34 Warning...it is not the disk0, check again, it is probably called Disk1 –Buscar웃 May 5 '15 at 19:37 add a comment| up