Help downgrading Monterey -> Sierra

[seinfeldseinfeld]

I bought a refurbished 2015 MacBook so that I could continue using my legacy software, but its SSD came preinstalled with OS 10.14 Monterey. I want to degrade it to 10.12 Sierra. I have a Time Machine / bootable external HD but can't work out how to erase the new SSD and put Sierra on it. I've tried everything, including creating a HFS partition on the SSD, but when I try to run disk utility from the external drive, it doesn't even see the SSD.

WHAT HAS BEEN TRIED:

• Booted in recovery mode - doesn't help, cannot restore Sierra onto the SSD.
• Booted from Sierra Time Machine backup external drive.
• Booted from a dedicated external Sierra boot drive.
• In all of the above, have tried "Restore", "Install New OS", and "Disk Utility"; in these attempts, the SSD drive doesn't appear as an option.
• I have tried within Monterey, partitioning the new SSD, creating a HFS partition in order to install Sierra on that. This generates error messages that appear to be some kind of incompatibility between Sierra and Monterey. EG, "Error 13" which appears to be some kind of Unix code.
• Or when I choose "Restore" to the new partition, I get the error, "Source volume format on device is not valid for restoring"

I'm guessing/hoping there is a set of commands in Terminal that will make the SSD visible while running the Sierra boot drive??

(This video seems to address the problem via BIOS settings but I can't work out how to get to the BIOS that he shows on the screen -

)

 

[ptfuzi]

Macs don't have an accessible bios.

You need to get Sierra installer onto a USB drive

 

[seinfeldseinfeld]

I have a Sierra installer on a CD drive. Problem is that (a) if I boot from it, it doesn't see the Monterey SSD that I'm trying to downgrade; (b) if i try to install onto a GUID partition on the SSD, it installs but won't boot (it gives the empty-set error).

 

[DeltaMac]

Boot to the Sierra installer.
You will need to remove/erase the APFS volumes (Sierra can't do anything with an APFS volume, hence your difficulty), so:
Open Disk Utility, then erase the internal device, not just the volume.
Choose the device - it will be the item at the top of the sidebar in that Disk Utility,look for the model number of the drive. Select that line, then erase, using Mac OS Extended (journaled)
When you have that internal drive back to a single volume, I would suggest that you then restart from the Sierra installer - then the internal drive should allow you to properly install Sierra, and you should be bootable this time.

 

[seinfeldseinfeld]

Thank you -
Question - how do I do this - when I open Disk Utility within Monterey and select the SSD as you say, the ERASE button is grayed out...??

 

[Fishrrman]

"when I open Disk Utility within Monterey and select the SSD as you say, the ERASE button is grayed out...??"

Hmmm...
You can't erase the drive that you're booted from.

I'm going to offer another approach.

Boot to A SPECIAL VERSION OF INTERNET RECOVERY:
Command-SHIFT-OPTION-R
... at boot.

Can you get to the internet utilities this way?

If so, open disk utilty.
IMPORTANT STEP:
Does disk utility have a "view" menu?
IF it does, go to it and choose "show all devices".
(If du DOES NOT have a view menu, it's safe to skip to the next step)

With disk utility, look at "the list on the left".
Do you see your physical SSD at the top of the list?

If so, click on it, then click the erase button.
Choose "Mac OS extended with journaling enabled, GUID partition format".
This should erase the ENTIRE drive.

IF that is successful, quit disk utility and open the OS installer.

IMPORTANT:
You booted to this special version of internet recovery, that is going to install the EARLIEST OS that shipped with the MBP you have.
It's a 2015, so I believe the OS that the installer will offer is 10.11 "El Capitan".

If that's the case, GO WITH IT for now.
The idea is to get a working, older OS onto it.
Start clicking through and see if El Cap will install.

If it does, you can TRY to restore from your backup.
That may not work (because the backup's OS is "newer than" El Cap).
But try it anyway.

If you can get El Cap "up and running" on the MBP, then you can "upgrade from there".

But you need to "wipe the drive clean" of the newer OS (and its drive partitioning structure) first.

With a "working El Cap", my next step would be to upgrade to 10.12 Low Sierra.
Either by way of a USB flash drive or just the OS installer in the applications folder.

A final thought:
Will your legacy software run with Mojave?
That's a very smooth OS, and the last to run 32-bit apps.

 

[DeltaMac]

Thank you -
Question - how do I do this - when I open Disk Utility within Monterey and select the SSD as you say, the ERASE button is grayed out...??

OP? You say Monterey, yet earlier you said 10.14... Is Monterey the name of your current boot volume?
10.14 is actually named Mojave, not Monterey (current release version for Monterey is macOS 12.4). Mojave is now an older version of the system. And, Mojave (10.14) would, in my opinion, be a good choice, particulary when you mention that you have older software that you want to continue to use.

 

[seinfeldseinfeld]

Thanks - I tried exactly that - the Internet Recovery loads Sierra and it does not have a view menu and does not see the SSD. :-(

 

[seinfeldseinfeld]

OP? You say Monterey, yet earlier you said 10.14... Is Monterey the name of your current boot volume?
10.14 is actually named Mojave, not Monterey (current release version for Monterey is macOS 12.4). Mojave is now an older version of the system. And, Mojave (10.14) would, in my opinion, be a good choice, particulary when you mention that you have older software that you want to continue to use.

Thank you for your question. The boot volume is definitely Monterey 12.4 - I get confused between the names and numbers of the OS. It is this Monterey-formatted boot SSD that Sierra cannot see when I do a recover or boot from Sierra to do a reinstall. And within Monterey, if I try to install Sierra from the Time Machine drive onto an HFS partition, it says that source drive is not valid.

 

[DeltaMac]

Monterey installed...
And you want Sierra installed as a bootable system, too?
You will need to add a new partition to the drive, with enough space for the Sierra install. It will need to be separate to the Monterey container,
So, you will need to boot to Monterey, and make a new volume, separate from the Monterey container, not just added to the Monterey boot volume. You will have to do this either while booted to Monterey, or booted to Monterey's recovery system. When you have that new volume for Sierra made, and if you have a Sierra installer on DVD, then boot to THAT, and reinstall Sierra. Assuming the DVD is set up properly (different users have different ideas on how to do that, as Apple never provided a Sierra installer on DVD, so someone has to discover how to do that (much easier to do make a bootable installer on a USB drive --- but, whatever works...), boot to that installer, install Sierra on the volume that you just made for that purpose.
Finally, when the install is complete, and your MacBook restarts, it will ask if you want to restore from a backup/Time Machine. Choose that. Should work, especially if it came from a system that was running Sierra when the TM backup was made.
And, there's the possibility that this won't install/boot correctly with Sierra. Then, you best choice will be to Erase the internal boot drive, so nothing on it. Split the single partition to whatever is your choice for space between the two systems. Install Sierra first on your choice of partitions, THEN install Monterey on the second volume (which will then change the Monterey volume to APFS. (Hopefully, the Sierra will work as above, and you won't need to start over completely )

 

[seinfeldseinfeld]

I don't mind erasing the entire drive and having it 100% Sierra. The problem is that when I boot from the Sierra HD (or Internet Recovery Mode), Sierra doesn't see the Monterey-SSD drive. It's invisible. I would love to erase the internal drive if you can teach me how to get Sierra to see it. (Is there another way to erase it?)

I thought I tried making a separate volume, maybe that's where I've made a mistake - while in Monterey, I created a partition and formatted it GUID - Extended (Journaled). Sierra doesn't see that either. Is there another way to make a new volume that you're referring to?

 

[DeltaMac]

I tried what you are trying. I had the same result: I have an internal drive with Monterey installed. I booted to a Sierra installer, and the internal drive/Monterey was not visible, even though there was a separate volume on that internal drive that was formatted Mac OS Extended, and also not a part of the APFS container. Nothing on the internal device appeared when I was booted to Sierra.
Here's what I found out... I then booted to a High Sierra installer, and the internal drive is now visible, and I can erase, or do anything else that I need to do with the internal drive.
If you still need to erase the internal drive (and you do need to erase that drive to do what you want with a Sierra system!), then you have to erase the drive with a system newer than Sierra. High Sierra will be successful.
Once the drive is erased (and you have reverted back to a Mac OS Extended format), then you will be able to install Sierra -- followed up with reinstalling Monterey. You will want to decide how much drive space you want for each system. I think you will also realize that you will perhaps struggle when choosing to boot from one system, then the other on the same drive. There would be workarounds to get that to work, too. If you want to have both systems, because of your legacy software, then that will be something that you will have to deal with.

 

[chrfr]

I don't mind erasing the entire drive and having it 100% Sierra. The problem is that when I boot from the Sierra HD (or Internet Recovery Mode), Sierra doesn't see the Monterey-SSD drive. It's invisible. I would love to erase the internal drive if you can teach me how to get Sierra to see it. (Is there another way to erase it?)

I thought I tried making a separate volume, maybe that's where I've made a mistake - while in Monterey, I created a partition and formatted it GUID - Extended (Journaled). Sierra doesn't see that either. Is there another way to make a new volume that you're referring to?

When you open Disk Utility, set the View menu to "Show all Devices." Then you'll see the entire disk and can erase it properly. This document will show you this info; even though it's for Big Sur, the details of what Disk Utility shows are close enough: https://support.apple.com/et-ee/guide/disk-utility/dskud6b39edb/20.0/mac/11.0

 

[DeltaMac]

That looks simple enough, but OP wants to use Sierra. Sierra Disk Utility does not show devices, there is no View menu, no option to Show Devices.
And, as I pointed out, the Sierra Disk Utility will not show any part of an internal drive that has Monterey installed. Sierra does not see the Monterey drive, even if there is a partition on that internal drive that is not APFS format.
OP will need to do that erasing using a higher version of macOS. (High Sierra would do the job, for example) Once the internal device is erased (removing the Monterey system from the drive), then an older system (Sierra) should install easily.

 

[seinfeldseinfeld]

Dear DeltaMac - THANK YOU. I so much appreciate your helping me with this. I haven't done it yet but I understand what to do and it seems simple enough (assuming I can find/create a High Sierra installer). Thank you.

 

[chrfr]

Dear DeltaMac - THANK YOU. I so much appreciate your helping me with this. I haven't done it yet but I understand what to do and it seems simple enough (assuming I can find/create a High Sierra installer). Thank you.

Given the apparent bugs in the Sierra Disk Utility, I'd just boot into internet recovery (command-option-R) and use that version's Disk Utility to format the disk with a single HFS+ partition using the directions I put into post 13, then boot back to your Sierra installer and proceed from there. This will be less work than finding a High Sierra installer and will accomplish the same thing.

 

[DeltaMac]

OP already tried Internet Recovery (post #8). Boots with Sierra, and same results -- that Disk Utility does not see the internal drive.

 

[Taz Mangus]

Dear DeltaMac - THANK YOU. I so much appreciate your helping me with this. I haven't done it yet but I understand what to do and it seems simple enough (assuming I can find/create a High Sierra installer). Thank you.

‎macOS High Sierra

‎New technologies at the heart of the system make your Mac more reliable, capable and responsive — and lay the foundation for future innovations. macOS High Sierra also refines the features and apps you use every day. It’s macOS at its highest level yet. Easily organise, edit and view your...

apps.apple.com

Create a bootable installer for macOS - Apple Support

You can use a USB flash drive or other secondary volume as a startup disk from which to install the Mac operating system.

support.apple.com

 

[Fishrrman]

If the OP has a USB flash drive with the Low Sierra installer on it, I'm thinking he could:
1. Get an EXTERNAL drive (either platter-based HDD or SSD)
2. Boot from the Low Sierra installer
3. Erase the EXTERNAL drive and install Low Sierra onto it (internal can be ignored for the moment)
4. Create an account on the external drive which he should now be booted from.
(The point here is to boot from an EXTERNAL drive that lets one "get to the finder")
5. Now open disk utility which should be able to "see" the internal drive (even if it can't mount it on the desktop)
6. Erase the INTERNAL drive
7. Use either CarbonCopyCloner or SuperDuper to clone the contents of the external drive to the internal drive.

All this is prefaced on whether the Mac, when "booted to the finder" from an EXTERNAL drive, can see the physical drive INSIDE the Mac (regardless of the OS that's on it).

I could be wrong in my approach.
If so, I'll reckon that DeltaMac's idea to create a High Sierra USB flashdrive, and then boot from that (which has the first version of disk utility that has "the view menu").
Then erase the internal drive to Mac OS extended with journaling enabled, GUID partition format.
Then -- either quit the installer or brute-force the power off.
Then -- boot from the Low Sierra installer, which should now be able to "recognize" the internal drive.

 

[DeltaMac]

I have an external drive, with installs for every Mac system from Leopard to Monterey. These are full system installs.
I have this to use for a variety of troubleshooting needs.
As I have stated above, if there is a Monterey system installed on an internal drive -- booting to Sierra from an external drive -- the Sierra system won't see the internal Monterey system drive at all, and Disk Utility on the Sierra system will not display anything about the internal drive that has a Monterey system. It has something to do with the APFS format, as there is some support for APFS in Sierra, but it is very minimal, and the Monterey boot drive setup is apparently completely mysterious to a Sierra system. Systems prior to Sierra see (something), but only in a very generic way (disk1, etc, just an unknown volume), but Sierra doesn't show anything about an internal drive with Monterey installed.
OP will need a Mac system installer newer than Sierra to erase the internal drive before Sierra can be installed.

 

[seinfeldseinfeld]

UPDATE - I think I followed your instructions -
1- used external HighSierra drive to erase the SSD; I made 2 partitions - a small one to leave for future possible Monterey and a large one (700gb) GUID / Extended-journaled
2- Booted from Sierra external HD - new SSD is still invisible to Sierra DiskUtility!
DeltaMac wrote "Once the drive is erased (and you have reverted back to a Mac OS Extended format), then you will be able to install Sierra" - this is where I think I'm stuck
3- Booted from HighSierra external HD - tried running Install Sierra - won't run on HighSierra.
4- Tried installing HighSierra on the SSD - High Sierra loaded fine, but it then reformatted it right back to APFS

I obviously did something wrong... what? Is the partition the problem?

 

[DeltaMac]

If you install High Sierra on the SSD, it will format to APFS, or change it to APFS, even if you purposely formatted as Mac OS Extended.

When you erased the SSD, did you change the View option to "Show all Devices", then choose the top line? That's the line that shows the manufacturer's info/model number of the device (and NOT the name of the partition.) If you don't erase the device, instead erase only the volume, then you still won't see the drive from Sierra. Did I say that's the top line under "Internal", You won't see that line unless you have the View menu set for "Show All Devices) You can't erase the internal device in Sierra -- must be High Sierra or higher. That is the only way to remove everything.

 

[Fishrrman]

OP:

Just a tip for the future.

Assuming you are able to get the Mac's internal drive bootable to Low Sierra again, I recommend that you DO NOT partition the internal drive and then install Monterey onto it.

Instead, get an EXTERNAL drive and install Monterey onto THAT.

It will work much better if you keep the OS's "separated".

 

[seinfeldseinfeld]

OK, I followed everyone's instructions -

1. I used High Sierra to reformat the ENTIRE ssd drive to GUID - Extended-journaled and did NOT create any partitions.
2. Then I booted the machine from a Sierra external drive and it does NOT show the drive.
3. Then I tried an internet recovery (took about an hour) and it failed with the following error message: "apple.com/support -5101F" ...
4. I retried using CMD-OPTION-SHIFT-R and that booted; however again, Disk Utility does NOT see the SSD drive.
(I tried "Install macOS Sierra" from the recovery menu, also doesn't show the SSD)
5. I rebooted with the High Sierra just to double check - again in its Disk Utility it shows the SSD top-level container as having "GUID Partition Map"

Help!

(is there a Terminal command that would allow High Sierra to run the Low Sierra install?)

 

[DeltaMac]

If there is a "container", that is an APFS container. You haven't erased the drive, just a volume on the container.
The only way to do this is to boot to the High Sierra installer.
Disk Utility - View menu - choose Show All Devices.
Choose the device, which will be at the top of the list (under Internal), and will be the line with the device information, such as manufacturer part number.
THAT's what you need to erase, the very top item, with the manufacturer's info.
If you still don't see that -- Post a screenshot (or a picture) here, so we can see what you see (while booted to your High Sierra installer.)