Using Disk Utility to unlock or decrypt your FileVault 2-encrypted boot drive
Bad things happen and sometimes those bad things cause your FileVault 2-encrypted Mac to be unbootable. In the event that you find yourself in this place, or you’re about to be, here’s how you can unlock or decrypt your FileVault 2-encrypted drive using Disk Utility and the password of an account that’s authorized to log in at the FileVault 2 pre-boot login screen.
1. Boot your Mac and hold down ⌘-R (Command –R) to boot from the Mac’s Recovery HD partition.
Note: You can also boot from a 10.7 installer drive , boot to Target Disk Mode and connect it via Firewire or Thunderbolt to another Mac, or use some other 10.7-booting drive. As long as you have 10.7′s Disk Utility, this should work.
2. Open Disk Utility.
3. Select your locked hard drive.
4. Under the File menu, select Unlock “Drive Name” or Turn Off Encryption… , based on what you want to do.
5. When prompted for a password, you can enter the password of any authorized account on the drive.
6. If you unlock the drive, you should then be able to use Disk Utility’s repair tools to hopefully fix the problem that’s preventing your Mac from booting.
7. If you turn off the encryption, the encrypted drive will decrypt. Once it’s finished decrypting, you should be able to access your data again using normal recovery methods (booting from another 10.6 or 10.7 boot drive, utility drive, etc.)
And when this does not work ?
My MacBook Pro went in to reboot and when it starts up I can choose between “My usersname” or “Guest”, but when I click on “My username” it just keep loading a bit and then show the Mac Stop sign.
I can log in as guest and log in trough Coomand+R, but when I try doing a “Reinstall Mac OS X” it show “Recovery HD” but “This disk is locked”
I use FireVault, can this also be an issue ?
I have the same question: what if this doesn’t work? I’ve booted from a Mountain Lion install flash drive and tried to partition the Macintosh HD, but this is not possible. The “Verify Disk” and “Repair Disk” runs with no error, but on the “Partition” tab all content is geyed out.
If I choose “Reinstall OS X” the only installable medium shown is the flash drive. The Mac. HD does not show up.
What to do?
If your Mac’s boot drive is encrypted with FileVault 2, you will need to decrypt it before installing (or reinstalling) OS X. You also need to decrypt it before Disk Utility will be able to repartition your drive.
Thanks for your answer. I have two possibilities: Hold the option button pressed and load the Flash Drive, then the Hard Drive is still encrypted. The “decrypt” and other options in the Disk Utility are greyed out as well as the partitioning tab. The other option is to boot into the hard drive. I enter the pass phrase and the mac tries to boot for a while, then shows a question mark and doesn’t do anything further. I am really annoyed at this point since I have to finish my paper till next week …
Any suggestions? You’ll be my hero.
You may want to see this other post: http://derflounder.wordpress.com/2011/11/23/using-the-command-line-to-unlock-or-decrypt-your-filevault-2-encrypted-boot-drive/
You, Sir, saved my weekend. Thank you a thousand times.
Couldn’t decrypt the FS anymore, so I totally erased it with “diskutil corestorage delete”. That’s totally ok for me, since my data is on an other drive.
Again, thank you.
Same here on saving my weekend. I also couldn’t decrypt the FS anymore, so I used what Martin posted “diskutil corestorage delete”. This worked for me.
Thanks everyone for the help!!!
Another option is to boot from your installation USB drive, then select the Apple and Startup Disk. Unlock your HDD from there, quit the Startup Disk utility and you’ll be back in the main installer. With Disk Utility you can then fully wipe your disk.
Thank you for this, which I hope is about to get me out of a major hole.
Two questions:
1. How long does the decryption usually take? It still says “converting” but there’s a disconcerting lack of disk activity.
2. After doing this will I automatically get a normal Mac login instead of a FileVault login screen?
Many Thanks
Ben
Ben,
It’ll take as long to decrypt as it did to encrypt. If the drive was having problems, it may take longer.
Once you begin decryption and reboot, you should be back to using the Mac’s regular login screen instead of the FileVault 2 pre-boot login screen.