Then this: diskutil erasedisk is the ID of your disk.Type this very carefully (sudo might not be necessary): sudo diskutil unmountDisk force /dev/disk2.(note: be EXTREMELY careful, ask you could wipe your computer if you do this wrong) I show in this video the solution to the disk disassembly problem in macOS.Solution Disk Erase Failed with error Couldnt unmount disk mac error 69888PTBR. Thankfully I ended up fixing it quickly (with a little googleing). Formatting a disk using Apples Disk Utility is the easiest and most straight-forward method of the two Navigate to the save file location on your workstation and double-click the installer file The MacOS X Installer program will start and ask for the root password mount -t vfat /dev/sda1 /mnt/sda1 NTFS-3G could not mount Fix NTFS-3G. I was getting things like: ”could not modify partition map” and “couldn’t unmount disk.” Other things could be things like “couldn’t open device.” Erasing an External USB or Hard Drive that keeps failing in Disk Utility You get this error, and the details vary depending on the format type you try That might be because the disk is a Windows/Linux bootable formatted as FAT-32, which OSX cannot read.Īnd then when you try to erase in disk utility, the USB is greyed out and First Aid doesn’t work, you can’t repair it, and you can’t mount or unmount it.
Are you trying to erase a USB drive on your mac but getting this error as soon as you insert it? eg sudo fsckexfat -d disk1s3 Disk Utility is a system utility for performing disk and disk volume-related tasks on macOS and Mac OS X systems Now you will enter the recovery mode, click on the disk utility option, and then choose the system drive and click on ‘verify disk’ If you suspect that something’s not quite right with your Mac.