Before choosing the best format for Mac external drive, you should know which file system formats are available in Disk Utility on Mac. Disk Utility supports the following file system formats: Apple File System (APFS): the file system is used by macOS 10.13 (High Sierra) or later.
I am using a Seagate Free Agent Desk external drive as my Time Machine on a modern iMac running Lion. I made the mistake of encrypting the drive, and I do not remember the password. I dont mind losing the data on the disk, and I just want to reformat it if possible in order to use it as a non encrypted drive. Any ideas on how to do this?Peter Štibraný
The encrypted volume's password is not required for erasing the disk, only to mount the encrypted volume on the disk. It's unclear whether you're being asked for the password only when connecting the disk, or when you attempt to erase it.
In Lion, you can use Disk Utility to erase an encrypted volume, but not in Mountain Lion. However, you can erase the encrypted volume with the
diskutil cs delete command (see Terminal section below) in both versions.
Disk Utility (Lion only)
The following steps should work in Lion:
Connect the disk to your Mac.
When prompted to 'Enter the password for the disk 'your disk',' click 'Cancel'. You don't need to mount the encrypted volume to erase the disk.
Open Disk Utility and locate your external disk on the left side. Its name will likely start with its capacity and include 'Seagate' or 'Free Agent' in the name. You should see your encrypted volume directly under the disk. The volume will be indented and grayed out.
Select the disk on the left side, not the volume.
Click the 'Erase' tab, found between the 'First Aid' and 'Partition' tabs. If you don't see the 'Partition' tab, and all the buttons under the 'Erase' tab are grayed out, double-check that you've selected the disk on the left side, and not the disk's volume.
Choose a format and enter a name, then click 'Erase'.
If this doesn't work, let us know which step is not working and how.
Terminal (Lion & Mountain Lion)
With the encrypted disk connected, launch Terminal and enter the following command
diskutil cs list
You should see output describing the encrypted disk, starting with info about the Logical Volume Group:
If you have more than one encrypted disk, locate the Logical Volume Group with the name of the disk you want to erase.
Copy the UUID which follows the words 'Logical Volume Group'. In this example this is the UUID for the disk named 'Le Disque':
WarningThe next command will erase the disk specified by the UUID you enter. Make sure you've copied the correct Logical Volume Group UUID for the disk you want to erase, especially if you have more than one encrypted disk connected.
Enter the following command to erase the encrypted disk, replacing
copiedUUIDwith the UUID you copied:
When complete, the disk will be partitioned with one volume mounted, called 'Untitled'. You can then start using it or repartition or encrypt it in Disk Utility as needed.
As joelseph said in his answer, you should be able to erase an encrypted volume in Disk Utility even without entering the password. However, I do not have a 10.8 system to test this with, and Ian C. said that 10.8 changed this.
If Disk Utility does prevent joelseph's answer from working, wiping out the partition table using the terminal is a viable workaround:
- Locate the drive in Disk Utility and click the Info button
- Find the Disk Identifier line and note what it says. It will say
#is a number.
Open the Terminal (in the Utilities folder) and enter the command:
#is the disk number from step #2. Double check this command! Then, triple check the command. Make sure the
disk#from step #2.
Press return and you will be prompted for your user password. Enter the password to begin erasing the partition table.
- After the process finishes (you will see a message
1+0 records in 1+0 records out 1048576 bytes transferred...) return to Disk Utility. You should now be able to format the drive.
This was confirmed to work in chat. Again, be very careful with the command. If you use the wrong disk you may erase valuble data.
You should never run terminal commands without understanding what they do. Here is a detailed explanation:
dd stands for Data Duplicate. It is a standard system command. See the Wikipedia Article and Manual page
if= specifies the input file to duplicate from.
/dev/zero is a special file (actually, a character device) which produces nothing but zeros (NULL characters)
of= specifies the output file to duplicate to.
/dev/disk2 or whatever is the external hard disk to overwrite.
bs=1024k specifies the block size, meaning write blocks of 1,024 kilobytes (1 megabyte). Writing blocks of 1 MB is simply faster than smaller blocks, that's why I close this size.
count=1 specifies how many blocks to write. 1 block of 1 megabyte is sufficient to overwrite the partition table, meaning Disk Utility will no longer know this is a password protected disk and will allow you to format it.
Lion's Disk Utility should be able to do this. My encrypted FreeAgent is at home.
Have you tried both erasing/reformatting the volume, and repartitioning the disk itself? Repartitioning should work.
I encountered the same issue. My best option would be to use another formatting utility from another operating system.
Starting the format from Windows wont care that mac has encryption on it.
After the partition is destroyed mac should be able to format it again.
Alternatively some Systems have disk utilities in the Bios. And you can use the manufacturers Low Level format utilities to erase the drive back to 0's. But Other than that. I think apple limits the format of encrypted mac drives. Likely to protect you from removing something that someone else encrypted. 'Perhaps there is a Special key you have to hold to enable the format' If not, Perhaps there should be.
You should be able to reformat this external drive with Disk Utility without any problems.JW8JW8
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Besides to open Bitlocker drive on Mac, M3 Bitlocker Loader for Mac can also use Bitlocker to encrypt USB drive, flash drive, external hard drive (The file system of external drive must be NTFS, FAT32, exFAT) on Mac. Tutorial to open Bitlocker drive on Mac. Following is the step-by-step tutorial to open Bitlocker drive on your Mac computer.
- Apr 18, 2019 Once it’s on the drive, it’ll automatically be encrypted and password-protected. Alternate method. Alternatively, you can also set the Format to Mac OS Extended (Journaled) and the Scheme to GUID Partition Map. This won’t encrypt your USB drive within Disk Utility, but it will allow you to encrypt it using the simple Finder method.
- Feb 21, 2020 Step 1. Connect the USB flash drive to your Mac computer. Step 2.Go to Applications Utilities Double click and open Disk Utility. Select your USB flash drive on the sidebar, choose Erase. Rename the USB flash drive, choose the format as MS-DOS (FAT) for Format, Master Boot Record for Scheme. Then click Erase.
'Is it possible to access BitLocker encrypted external hard drive on macOS, Linux, Android or Windows Mobile? I have an external hard drive that has been encrypted with Bitlocker on a previous work laptop. The problem is that I don't have the laptop anymore. I can't open Bitlocker encrypted external hard drive on the Mac now and not sure if there is a program or way around the password to unlock Bitlocker encrypted external hard drive on macOS?'
Bitlocker for macOS & Mac OS X
BitLocker is a full disk encryption feature included with selected editions of Windows Vista and later. It is designed to protect data by providing encryption for entire volume. By default it uses the AES encryption algorithm in cipher block chaining (CBC) mode with a 128-bit or 256-bit key.
Is Bitlocker supported on Mac?
The answer is Yes, but it needs the 3rd party Bitlocker for Mac tool, please read on...
Microsoft only released Bitlocker for Windows version and has not implemented Bitlocker for Mac version, so macOS and Mac OS X cannot recognize Bitlocker drive encryption so that you cannot open Bitlocker drive on your Mac.
However, with the help of the 3rd party tool: M3 Bitlocker Loader for Mac, Bitlocker is compatible with macOS and Mac OS X so that you can open Bitlocker drive on your Mac computer and use Bitlocker to encrypt USB drive on your Mac.
Open Bitlocker drive on Mac
M3 Bitlocker Loader for Mac can easily open Bitlocker drive and then enable to read/write Bitlocker drive on macOS Catalina 10.15/Mojave 10.14/High Sierra 10.13/10.12 and Mac OS X 10.11/10.10/10.9/10.8 Operating Systems after providing the password or recovery key, whichever it is on Mac Mini, Mac Pro, MacBook, MacBook Pro, MacBook Air, iMac or iMac Pro.
Use Bitlocker to encrypt external drive on Mac
Mac Os X Encrypt Usb Drive
Besides to open Bitlocker drive on Mac, M3 Bitlocker Loader for Mac can also use Bitlocker to encrypt USB drive, flash drive, external hard drive (The file system of external drive must be NTFS, FAT32, exFAT) on Mac.
Tutorial to open Bitlocker drive on Mac
Following is the step-by-step tutorial to open Bitlocker drive on your Mac computer:
Step 1: Download M3 Bitlocker Loader for Mac on your Mac computer.
Step 2: Double click the installation package and follow the wizard to complete the installation.
Step 3: Launch M3 Bitlocker Loader for Mac from Applications folder or launchpad.
Step 4: Insert a Bitlocker drive (USB drive, flash drive, external hard drive) into your Mac computer.
M3 Bitlocker Loader for Mac requires a healthy Bitlocker drive. If your Bitlocker drive has been corrupted, please try Bitlocker data recovery software: M3 Data Recovery in Windows to recover lost data from corrupted Bitlocker drive.
Step 5: After inserting the Bitlocker drive, choose 'Ignore' if you receive message 'The disk you inserted was not readable by this computer with three buttons: Initialize, Ignore, Eject'.
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Step 7: Enter the password (or recovery key) and click 'Unlock' to unlock Bitlocker drive.
If it is Bitlocker encrypted OS drive, the recovery key is the only way to open Bitlocker drive on Mac.
Format Encrypted Usb Drive Mac Free
If you lost the password and recovery key, M3 Bitlocker Loader for Mac cannot break into the Bitlocker drive, please refer to how to unlock Bitlocker drive without password and recovery key?
Step 8: After mounting the Bitlocker drive on your Mac, you can read or write Bitlocker drive in Finder like a native drive.
The files will not be protected from the Bitlocker drive encryption once they leave from Bitlocker drive and the files will be automatically encrypted after copying from your Mac computer to the Bitlocker drive.
Step 9: After reading/writing Bitlocker drive, please click Lock button in M3 Bitlocker Loader to lock your Bitlocker drive.
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Bitlocker for Linux/Ubuntu
M3 Bitlocker Loader for Linux is a command line tool to encrypt USB drive, flash drive or external hard drive with Bitlocker and open Bitlocker drive in Linux/Ubuntu.
Tutorial to open Bitlocker drive in Linux
Step 1: Download M3 Bitlocker Loader for Linux installation package.
Sandisk Usb Encryption Software
Step 2: Insert a Bitlocker drive into your Linux computer.
Step 3: tar -xvf m3.bitlocker.linux.tar ./
Kingston Encrypted Usb Flash Drive
Step 4: cd m3.bitlocker.linux
Step 5: ./install.sh
Step 6: Enter the command to open/access Bitlocker drive in Linux: m3.bitlocker [device name] [mount path] [volume name] [password]
Bitlocker for Windows Home
M3 Bitlocker Loader for Windows is a free encryption software to create an encrypted container which is compatible with Bitlocker Drive Encryption so that the USB drive, USB flash drive or external hard drive is protected by Bitlocker in Windows 10/8/7 Home and Windows 7 Professional.
Mac Os X Encrypted Usb Flash Drives