#COULDNT UNMOUNT DISK MAC OS MAC OS#
#COULDNT UNMOUNT DISK MAC OS INSTALL#

I suggest using Ethernet if possibleīecause it is three times faster than wireless. Note : You will need an active Internet connection. gpt destroy: unable to open device '/dev/disk2': Permission denied It seems to me there is some lock on device disk2. start size index contents 0 7741440 Running gpt destroy /dev/disk2 yields.

#COULDNT UNMOUNT DISK MAC OS INSTALL#

Reinstall Lion/Mountain Lion, Mavericks : Select Reinstall Lion/Mountain Lion, Mavericks and click on the Install button. Started partitioning on disk2 Unmounting disk Error: -69877: Couldn't open device Running gpt show -l /dev/disk2 yields. The Erase button and wait until the process has completed. Obviously there is some process on disk0s1, disk0s2 or disk0s3 blocking the unmount command and the following efforts to force unmounting. In recovery-mode he tried 'diskutil secureErase 0 /dev/disk0' resuming 'Error: -69888: Couldn't unmount disk'. The Security button and set the ZeroData option to one-pass. I'm trying to help a friend formatting a hard disk.

#COULDNT UNMOUNT DISK MAC OS MAC OS#

Set the format type to Mac OS Extended (Journaled.) Optionally, click on Click on the Erase tab in the DU main window.ģ. After DU loads select your startup volume (usually Macintosh HD) from the Select Disk Utility from the main menu and click on the Continue button.Ģ. In the Disk Utility app on your Mac, select the disk set that you want to unmount in the sidebar. Install or Reinstall Mavericks, Lion/Mountain Lion from Scratchīe sure you backup your files to an external drive or second internal drive because the following procedure will remove everything from the hard drive.ġ. This should unmount the drive so you can now do this: For a single drive system this will probably be /dev/disk0. You should also see the name of the disk such as 'Macintosh HD.' Note down the disk identifier. If will look like /dev/diskn/ where 'n' is an integer starting at 0. From the listing look on the left column for your disk identifier.

If you are, then you neeed to do the following: In case, if you’re using an installer disk instead of a USB bootable drive, then pull down the Utilities menu in order to access Disk Utility. Using Disk Utility I deleted the 'Data' volumes first, but when I try to erase the main volume (which has been named 'Catalina'), I get. I have followed the instructions on the Apple website. Are you booted from the Recovery HD partition? If not, then you need to first boot from the Recovery HD before you can erase the Macintosh HD. Here, the USB bootable drive is referred to as a pen drive, or USB stick which should have Mac OS installed in it. Having set myself up as the User I am assuming that I can't just delete that account (correct) and that I have to erase the disc and reinstall the OS. Back up as many of your files as possible, reformat the disk, and restore your backed-up files.OK, Relax.

If you have any idea to get the HDD working or even safe the files, I would be really grateful.Īlmost forgot about this from Disk Utility:ĭisk Utility can’t repair this disk.

This was the try: $ sudo diskutil eraseDisk JHFS+ DISK_VOLUME disk1īut it didn't work as well. If you see an error message telling you that macOS couldn’t unmount a disk, it usually means that a process on your Mac is trying to modify your boot disk and can’t because macOS won’t allow the disk that it has booted from to be unmounted. Than for each disk: $sudo diskutil unmount force disk1snīecause I wasn't able to do anything with my external HDD I made a desperate attempt to erase everything on it, including unbackuped files, cause this used to be the backup plan. Gave this: Forced unmount of disk1 failed: at least one volume could not be unmounted 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.Ģ: Apple_HFS Macintosh HD 140.0 GB disk0s2ģ: Apple_Boot Recovery HD 650.0 MB disk0s3Ĥ: Microsoft Basic Data BOOTCAMP 110.1 GB disk0s4Īnd then to unmount this: $sudo diskutil unmountDisk force disk1

My 1TB LaCie Rugged THB decided it was a good idea to stop working all of a sudden.

Couldnt unmount disk mac os