hard drive – After converting SSD to APFS MacBook 2014 doesn’t boot anymore

Good morning,

My MacBook 2014 with TouchBar doesn’t boot anymore when going from its original Sierra to newer operating systems, e.g. High Sierra or Big Sur. One morning the computer just refused to boot, and got stuck in the login process. I was able to still log in, sometimes, but after opening an app, the Mac gave a kernel panic. Various tests later, reformatting the drive, and resetting everything, eventually I was able to use Internet Recovery, to install the original Sierra OS, which still uses HFS+. Naturally I tried installing Big Sur first, but got the same issues right after upgrading. I then tried going in steps, using gibMacOS, from Sierra, to High Sierra. But even High Sierra produced the same issues. I was in Disk Utility that installing High Sierra, already formatted the drive to APFS, so my conclusion now is that something makes the computer stop working after the converting to APFS.

Ideally I would love to get Big Sur again up and running, but I don’t know what steps I can take to make that happen. My hunch is that some sectors on the drive are just so damaged, because of wear and tear that it’s now impossible to get it formatted to APFS. I hope I’m wrong though.


MacBook refuses to boot after its drive gets converted to APFS it seems. Restoring Sierra makes the computer work again, but any upgrading attempts to High Sierra or Big Sur, resulted in the same issues the Mac had, which started this entire problem.

macos – 10.13 to Big Sur – HDD APFS System volume and HFS+ User Space

I want to install either 10.15 or Big Sur on a small APFS partiton on an internal HDD in a Mac Mini. I’ve clean installed OSX and many other OSses before and am quite comfortable installing OSes.

I’m on an older OS X version and some updated applications I use are now 10.15 or higher. There’s only one OSX install on the drive and I don’t want to dual-boot the system.

Since one APFS partition is now mandatory for the System Partition, I would like to meet the mandatory requirement. I don’t see why the rest of the system cannot have one or more discrete HFS+ partitions for user data and applications.

Would the following Partition layout work?

HDD Volume
Partition1 > OSX System Volume > 60 GB (I think Big Sur installer says 20 GB is minimum)

Parttition2 > HFS+

Partition 3 > HFS+

catalina – hdiutil fails to create APFS sparseimage: “no mountable file systems”

In macOS Catalina (10.15.7), I’d like to create and mount a sparse, writeable disk image that uses APFS.

This works:

$ -> hdiutil create -attach -size 10m -fs APFS -type UDIF "Test.dmg"
/dev/disk7              GUID_partition_scheme           
/dev/disk7s1            Apple_APFS                      
/dev/disk8              EF57347C-0000-11AA-AA11-0030654 
/dev/disk8s1            41504653-0000-11AA-AA11-0030654 /Volumes/untitled
created: /Volumes/Backups/Test.dmg

This works, too:

$ -> hdiutil create -attach -size 10m -fs HFS+ -type SPARSE "Test.sparseimage"
/dev/disk5              GUID_partition_scheme           
/dev/disk5s1            Apple_HFS                       /Volumes/untitled
created: /Volumes/Backups/Test.sparseimage

This does not:

$ -> hdiutil create -attach -size 10m -fs APFS -type SPARSE "Test.sparseimage"
hdiutil: create failed - no mountable file systems

I’ve searched the man page, but can’t find any clues about what I’m doing wrong. Any suggestions?

Update: It works if I create Test.sparseimage on my local disk. I’m just unable to create it on a NAS volume.

permission – Can’t open folder on (encrypted) APFS drive in Finder after sharing through SMB and setting “Everyone” to “Read Only”

I have a folder that I use to backup my Android phone to. It is shared over SMB. Until recently this folder resided on an old Time Machine drive formatted as HFS+.

I’ve now moved the folder to a new drive formatted as APFS with encryption. I’ve configured the share the same way I did on the old drive: my user and “staff” can read and write, and everyone else has no access. The folder and its contents are “owned” by my user.

However, when I open the drive in Finder, the folder is marked with a “no entry” icon and when I try to open it I get the following message:

The folder <folder_name> can’t be opened because you don’t have permission to see its contents.

When I add “Read only” to everyone and select “Apply permissions to Enclosed Items”, I can navigate the folder and its nested content as before.

What can I do to allow navigation in Finder without allowing everyone read access to those shares?

For now I can work with the “Read Only for Everyone” work-around, but I’d much prefer not to. The only real difference I see is the formatting of the two drives, but I have now real idea whether that has any influence on this behaviour.

hard drive – My APFS won’t boot, please help

Please help me @davidanderson , or anyone else who can help me with my problem.

I found your advice on this page: Lost my APFS partition after using EaseUS partition manager on Bootcamp

I did the same thing – used EaseUS to reformat a windows drive to be larger, and made my APFS unbootable. I followed the instructions:

From Windows, you can open a Command Prompt window as an Administrator. Next, you could enter the commands given below to change disk0s2 to an APFS type.
select disk 0
select partition 2
set id=7C3457EF-0000-11AA-AA11-00306543ECAC override
gpt attributes=0x0000000000000000

Which recovered my APFS drive perfectly. I also had a partition (number 3 on disk 0) and it was an OS X Journaled Extended drive (Which I think is HFS+). Frantically, I ran the same script above changing that drive to APFS, which is still unusable.

I’m so clueless and trying to scour the internet to figure out how to change the drive back to HFS+ so it can be accessed again. Thanks in advance!

ssd – Is it possible to manually TRIM the free space for an existing APFS volume?

When migrating a MacBook from HDD to SSD, I did a block-level copy using dd. Because the SSD already contained a different OS image from a previous test, I believe for optimal performance, it would be the best to issue a TRIM for every unused block in the new filesystem to inform the SSD controller. Is it possible to TRIM the free space manually for an AFPS volume on macOS (like FreeBSD’s trim or Linux’s fstrim)?

I’ve read that macOS’s fsck has a TRIM pass, so TRIM can be triggered manually by running fsck -fy in single-user mode. But I didn’t see any message about TRIM when I tried it, so I guess it’s only applicable to HFS+ filesystems.

macos – Tutorial: Fix Mac OS Big Sur APFS Partition Issue

Like many people online, I’ve been having issues with resizing my APFS Partition ever since Big Sur (11.1 BETA). There was a point in time where I had 500GB of unusable free space that I couldn’t allocate to my functional partition of Big Sur!

A Little Background About the Issue (Skip if you don’t care):

Not too long ago I installed the Mac OS Big Sur Developer Beta on my computer. It was alright – a few issues here and there, but nonetheless not bad for a beta. After Big Sur was officially released, I wanted to get out of the Beta and remain on the public version of Big Sur. Of course, that’s no easy task. So what I decided to do was partition my drive (500/500), install the public version of Big Sur on the new partition, and then move all my files over – It worked! Now it was time to resize the new partition after formatting the old one so that my new partition was the full 1TB of available space – and that is where this tutorial will help. For some reason, with Big Sur, I was unable to change the size of the Partition. I tried every single command-line google had to offer – I even went as far as using Recovery to run GPT commands. The furthest I got from that was the ability to recover the “Free Space” and use the 1st partition as a drive, but it was still considered separate from my main Big Sur partition. So here’s what I did.

What you’ll need:

  1. A Second Mac (With enough storage to backup your files)
  2. A Bootable USB Big Sur Drive (Apple has great docs on how to make that)
  3. A Thunderbolt cable (and respective adapters to establish a connection between the first (Problem Mac) and second Mac)
  4. Time

Before you start just know that you will lose your preferences and installed Apps (Some apps may be transferred by the methods below). If you use Time Machine, you might be able to hold onto your preferences and Apps.

You may be able to use a time machine backup, but I haven’t tested it. If you want to use a time machine backup, Mount your Troubled Mac (covered in Step 1) and then skip to Step 2.

Step 1

From the Troubled Mac: Turn off your issued Mac, then turn it on and immediately hold down ‘T’ on your keyboard. Plug in your thunderbolt cable.

From the Second Mac: Plug in the other end of the thunderbolt cable, go to disk utility, find the Hardrive(s)/partitions of your troubled Mac, Right-click on all partitions and choose “Mount” – You may be asked to enter the password for the drives. Right click on the “-Data” drive and choose “Show in Finder”. Navigate to your home directory where you’ll find all your files.

Continuing on the Second Mac: Make a new folder in a safe spot. Move over all your files from the issued Mac (“Show in Finder” Finder Window). Patiently wait until you have secured a copy of all your files on the Second Mac.

Step 2

This step may be able to be completed from Recovery/Bootable Installer command-line. Not Tested

From the Second Mac: Open up terminal and type in

diskutil list

You’ll get a list of all the drives, including the attached Target Disk (Troubled Mac). Note the disk identifier of the troubled Mac (In my case it was disk3; yours may be different). With your Partitions still mounted through Disk Utility, type in the following command:

diskutil partitionDisk disk3 1 GPT HFS+ Untitled 100%

This will format the troubled mac’s SSD/HDD to an HFS+ partition. Note: If you receive the “Can’t open” error, double check that the troubled Mac is A) Mounted in Disk Utility and B) Not being used by another application such as a Recovery Program or Transferring Files!

Once completed, you’ll see the new “Untitled” drive in Disk Utility, formatted as an HFS drive. Select the new “Untitled” drive in disk utility and click “Erase” along the top menu. Choose to erase as “APFS” (Don’t choose encrypted) and Give it a nice title – How about “Macintosh HD”. Click “Erase”. You’ve fixed your hard drive Allocation/Partition Problem!

Step 3

From the Troubled Mac: Hold down the power button for 10 seconds to shut off the computer. Plug in the Bootable Installer USB. Turn on the Mac and hold down the “Option” key until you see the Bootable Drive. Select it. Install Mac OS Big Sur Public as normal. Set it up and Log yourself in. Wallah! A fresh Mac that is the full hard disk size!

Step 4

If you are using a time machine backup, restore from Time Machine and you should be good to go!

There is a good video by 9to5mac on how to do this step if you are not using a time machine backup

With your newly formatted Mac still plugged into the Second Mac, go to System Preferences on Both Macs.

On Both Macs: go to network settings and click “+”. Add a thunderbolt bridge connection. Note the IP address from the Second Mac.

On The Second Mac: Go back to Sharing Preferences. Check mark “File Sharing”.

On The Newly Formatted Mac: Go to Finder. Hit
“Go” in the top menu bar, then select “Connect to Server”. Enter the IP address you noted from the Second Mac and hit “Connect”. After a few moments you’ll be asked to login, in which you’ll enter the credentials for the Second Mac. The Second Mac should now be mounted as drive on the Newly Formatted Mac where you can move your files back over to their respective folders.

Finished! If you’ve made it this far, I know you were as desperate as I was. I hope this was able to help a few of you – And for those of you that knew this, WHERE WERE YOU WHEN I NEEDED YOU?! Let me know if this worked out for you. Happy Big Sur-ing.

Stop macOS from creating synthesized disks from an APFS partition?

I have a raw dump of an APFS partition that I’ve created so that I can roll back a system to an exact state for testing. This dump was created using dd, and is not created form any of the volumes inside the container, but rather the entire APFS partition from the physical disk.

I’d like to restore it back on to the physical disk using dd, and normally I would do this by simply unmounting the partition so that the system isn’t accessing it anymore. But because macOS is automatically creating a synthesized device from this APFS partition that contains all of its volumes, I can’t restore it without the system going nuts as the partition’s data changes out from under it.

How can I stop macOS from automatically creating the synthesized disk so that I can freely modify the raw data of this partition?

For example, if this is what diskutil list reports:

/dev/disk2 (external):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                         500.3 GB   disk2
   1:                        EFI EFI                     314.6 MB   disk2s1
   2:                 Apple_APFS Container disk1         499.9 GB   disk2s2

/dev/disk3 (synthesized):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      APFS Container Scheme -                      +499.9 GB   disk3
                                 Physical Store disk2s2
   1:                APFS Volume MyDisk                  462.0 GB   disk3s1
   2:                APFS Volume Preboot                 43.9 MB    disk3s2
   3:                APFS Volume Recovery                510.5 MB   disk3s3
   4:                APFS Volume VM                      2.1 GB     disk3s4

… then I want it to stop “synthesizing” /dev/disk3 completely. Unmounting the volumes disk3s1disk3s4 is not good enough. And diskutil won’t let me unmount /dev/disk3.

So far the only solution I’ve found is to do this on macOS 10.12 or earlier, since that system doesn’t know about APFS. But I’d much rather do it on my main system running 10.14.

macos – How do I decrypt an APFS volume that’s marked “Encrypted at rest” (T2-equipped Mac)

See also: What does “FileVault: No (Encrypted at rest)” mean?

As a developer and researcher, I need some APFS volumes on a T2 Mac decrypted to the point that reading their raw blocks, e.g. with the dd command, will show me the unencrypted content. How do I achieve that, provided I have full access (and authentication) to the Mac and its on-disk data?

I’d either need a way to decrypt the blocks after reading them (e.g. from /dev/diskXsY), or would need to have macOS decrypt them fully, just like some hidden volumes (“Preboot”, “Recovery”, “VM”) are already by default.

With pre-T2 Macs this was easy: I would issue the command diskutil apfs decrypt diskXsY. But on a T2 Mac, this leads to the message:

APFS Volume diskXsY is not FileVaulted

How do I get raw access to the unencrypted content of these volumes’ blocks? Be it by using some command to decrypt them permanently, or getting the information on how to write code to decrypt the blocks on-the-fly.

Note: I do not plan to remove the SSD from the Mac – I just want to be able to scan the APFS structures of these volumes while they’re inside that Mac, and for that I need them decrypted.

Another benefit of answering this question: Decrypting the volumes permanently should enable a user to clone the raw disk (i.e. its containers) to another Mac, where one could then re-encrypt the data (if there’s a process for that).