<< Solved >> Accidentally deleted Preboot volume, could not upgrade MacOS X anymore.

[nickboy]

Hi,

I accidentally deleted the Preboot volume under /Volume, so when I tried to upgrade the MacOS X from "macOS install Prebooter from Preboot" in clover menu which showed the prohibited sign.

I have been searching the potential solution on the Internet but no luck. Does anyone know how can we recover the Preboot volume so I can upgrade the MacOS X again? Or reinstall the whole system is the only way to go?

Mac OS X: 10.15.4 (tried to upgrade to 10.15.5)
Clover version: 5118

Any suggestions/tips will be greatly appreciated.

 

[Namok88]

You can't recover it.

Is your system APFS? If it is you can still boot from a USB installer, create a new volume, and install a new system in it. It will create the Preboot volume again.

 

[nickboy]

You can't recover it.

Is your system APFS? If it is you can still boot from a USB installer, create a new volume, and install a new system in it. It will create the Preboot volume again.

Thanks for replying, yes my system is APFS. So you mean that I can create a new volume by reinstall the system again. Does it mean that I can just reinstall it without removing the contents on my computer or I have to do a brand new installation?

 

[Namok88]

You must create a new volume on the APFS container with Disk Utility and fresh install a Catalina in it.

It should end up creating the Preboot partition when it detects that it is missing.

If that worked, you can delete this new volume.

Give it a name that is easy to not confuse with the one that contains your data.

 

[Archangeliques]

Thanks for replying, yes my system is APFS. So you mean that I can create a new volume by reinstall the system again. Does it mean that I can just reinstall it without removing the contents on my computer or I have to do a brand new installation?

You may want to use Time Machine backup before doing so, so you'll have all your files, settings etc backed up and ready to be restored when you fresh install any macOS version.

 

[Namok88]

You may want to use Time Machine backup before doing so, so you'll have all your files, settings etc backed up and ready to be restored when you fresh install any macOS version.

That's what OP would have to do if the Preboot volume isn't getting created with that fresh installation in the temporary volume.

 

[Archangeliques]

That's what OP would have to do if the Preboot volume isn't getting created with that fresh installation in the temporary volume.

It doesn't matter whether Preboot created or not, TM backup will save one's life (esp. if OP worries about his/her data) in any case.

What I would do:

- Get backup with TM (alternatively other tools can do the job too but TM is native and less prone to have issues with),
- Get EFI backup
- Download the latest macOS from the App Store.
- Create USB Install
- Make fresh install and save myself trouble of trial and error (creating another volume and installing new OS and praying for it to create Preboot volume etc.)
- Once installation completes, do the post installation, EFI etc. Then start Migration Assistant and follow the steps from below.

How to move your content to a new Mac: Use Migration Assistant, Time Machine Backup https://support.apple.com/en-us/HT204350

 

[nickboy]

Thank you guys for the suggestions, it turned out that I have to select "(System Volume name) - Data" volume for continuing the installation.

Even though I got "the bless tool was unable to set the current boot disk. -69793)" error, but I was able to install the updates successfully.

Still searching the solution on this issue, and not sure if it will happen when I do a fresh installation.

Found a discussion about the bless tool issue on the forum, maybe it's because of my Z390 chipset.

“The bless tool was unable to set the current boot disk” error message after installation

Clover configurator Rt Variables CsrActiveConfig 0x67 I hope your memory fix driver also fixes nvram issues with Z390 chipset Even though I am new to opencore it its looking good On my Asus Z390 system, I have CsrActiveConfig 0x67, AptioMemoryFix.efi and EmuVariableUefi.efi running...

www.tonymacx86.com

 

[Namok88]

@nickboy

I gave you a solution that is safe for your data since Catalina now creates a read only system volume and a read/write data volume for users that is the same name as the system volume with an extra "- Data" at the end. They are both linked with firmlinks. So when you boot with Catalina Install Disk (not update) and you create a new volume in your main APFS container, it will not interfere with the other volumes. It will just create the one it needs. When the installation is done you'll have 2 Catalina system volumes and 2 Catalina user data volumes. Both will be bootable.

So you'll just have to normally boot on your original Catalina (that contains your data) and only delete the volume that contains the freshly installed one.

@Archangeliques

You forgot one important detail. OP can't boot on his current Catalina (even if he tries to pray harder).
So there's no way for him to be able to do a TM backup to save his current data.
Unless he has another computer running Catalina 10.14.4. He would have gone that route already.

So the proper way is to

* create another volume in his APFS container
* give it a specific name (so he won't confuse it with the current non-bootable Catalina that contains his data)
* install another Catalina in that new volume

and then he can try to boot on his original Catalina when the install is done.
In the case it didn't work, he will still be able to boot the freshly installed one, run TM backup and save his current data on an external volume.

 

[Archangeliques]

Thank you guys for the suggestions, it turned out that I have to select "(System Volume name) - Data" volume for continuing the installation.

Even though I got "the bless tool was unable to set the current boot disk. -69793)" error, but I was able to install the updates successfully.

Glad that you successfully updated your OS. If you can boot on your desktop backup with TM immediately then you may want to follow what I suggested earlier for not having similar issues with next updates.

@Archangeliques
You forgot one important detail. OP can't boot on his current Catalina (even if he tries to pray harder).
So there's no way for him to be able to do a TM backup to save his current data.
Unless he has another computer running Catalina 10.14.4. He would have gone that route already.

and then he can try to boot on his original Catalina when the install is done.
In the case it didn't work, he will still be able to boot the freshly installed one, run TM backup and save his current data on an external volume.

Yeah, I thought he can still boot on desktop but cannot update.

How come fresh install can access old install's user data (documents, desktop, etc.)? Even in Windows any files under Users folder cannot be accessed from a new installation. One needs to take ownership etc. to overcome permission issues. On Mac, this would be harder.