How to Fix Could Not Create a Preboot Volume for APFS install Error

The ‘Could not create a preboot volume for APFS install’ error message in macOS occurs when the operating system tries to change the format of the boot disk, which it isn’t able to complete successfully.

The issue can also arise if the preboot and recovery volumes on your disk are not mounted prior to the installation. In this guide, we will show you a few methods that can help you resolve the above error message while installing macOS. 

1. Format Disk to APFS

The first thing you should do is to format the disk to the correct format for the installation wizard to complete. Apple File System (APFS) has become the default format for bootable and data volumes since macOS 10.13. As such, if you are updating your macOS to a later version, you will need to ensure your disk is formatted correctly.

Note: It is vital to note that formatting your disk will erase all of the data inside. Therefore, we recommend backing up any important data on your drive before proceeding. 

1. First, you will need to boot into the macOS Recovery menu.
2. Press and hold down the Power button on Macs with Apple silicon until the device boots into the Startup Options screen.



3. Click Options and then hit Continue.



4. On Macs with older chips, restart your Mac with the Command + R keys pressed.
5. This will boot your device into recovery mode.
6. From the menu, select the Disk Utility option.



7. Then, in the Disk Utility app, click the Show All Devices option.
8. Select your disk and click the Erase option.



9. After that, select APFS from the Format menu.



10. Finally, click Erase again to proceed.
11. Wait for it to complete and see if the error message occurs again. 

2. Mount Existing Preboot and Recovery Volumes

Another cause of the issue can be the preboot and recovery volumes on your disk. This happens when the volumes are mounted as read and write instead of read-only. To fix this, you will need to remove the write permissions on the volumes before running the macOS installer.

1. First, open a Terminal window in macOS.



2. Then, type in the following commands one by one in the Terminal:

diskutil mount Preboot 
diskutil mount Recovery 
sudo mount -uw /Volumes/Preboot 
sudo mount -uw /Volumes/Recovery

3. If you encounter the “sudo: command not found” error message, you are using the recovery mode. In this case, enter the commands without the sudo keyword. 

3. Format Disk to MacOS Extended

Older macOS used the MacOS Extended format for boot volumes. Thus, if you are upgrading from an older version of macOS, you will need to ensure the disk is formatted to MacOS Extended (Journaled). You can do this quite easily via the Disk Utility app.

1. On older Macs, start by restarting your Mac with the Command + R keys.
2. If you have an Apple silicon Mac, power it off and then press and hold down the Power button till you see the Startup Options screen.



3. Select Options and then click Continue.



4. In the recovery menu, open the Disk Utility app.



5. Then, select your disk and click the Erase option.



6. After that, choose MacOS Extended (Journaled) as the Format option.
7. Finally, click Erase to format the disk. 
8. Once complete, run the installer to see if the issue continues. 

4. Reinstall MacOS in Recovery

Finally, if the above methods do not help isolate the issue, you can reinstall MacOS via the recovery options on your device. Reinstalling macOS via the recovery mode does not remove any of your data, so there is nothing to worry about.

1. First, boot into the macOS Recovery menu.
2. On Macs with Apple silicon, power off your device. Then, press and hold down the Power button until you are taken to the startup options screen. Click on Options and then click the Continue button.



3. For older Macs, restart your device while pressing the Command + R keys on your keyboard. 
4. After that, in the macOS Recovery menu, select the Reinstall macOS option.



5. Follow the on-screen instructions to complete the installation.
6. See if the issue occurs again during the installation.

These solutions should help you isolate the ‘Could not create a preboot volume for APFS’ install error message on your Mac. If you continue to encounter the error, we recommend reaching out to the official Apple support team for further assistance regarding the problem.