So I am using Samsung T7 trying many different ways to install OS 26 so I can recover my former MBP and also use the external SSD as a bootable device but it's sure not letting me and I am irritated that I can't get this thing working. Why what am I doing wrong?
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Why can't I install Mac OS 26 onto external and boot from it?
- Thread starter tbluhp
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Did you create macOS Tahoe USB install media onto the Samsung T7 and are trying to run the installer from the T7 in order to reinstall macOS Tahoe onto your MBP? Or are you trying to install macOS Tahoe onto the T7 and boot from the T7? It's not clear from your run on sentence.
Install macOS on an external storage device and use it as a startup disk - Apple Support
If you have an external storage device, you can set it up as a Mac startup disk.
I downloaded the latest 26.0.1 from terminal (called apple support) once that downloaded to applications folder I clicked on the application and ran install. That's how I am doing it.
What apple told me is a complete lie even from a senior advisor. She told me to rename the external hard drive MyVolume then reformat the external to Mac extentedend (Journaled) not APFS which the installer clearly state needs to be installed on a APFS drive.
This is the terminal command she provided
sudo /Applications/Install\ macOS\ Tahoe.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume
complete waste of time. I have another call scheduled later today.
What apple told me is a complete lie even from a senior advisor. She told me to rename the external hard drive MyVolume then reformat the external to Mac extentedend (Journaled) not APFS which the installer clearly state needs to be installed on a APFS drive.
This is the terminal command she provided
sudo /Applications/Install\ macOS\ Tahoe.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume
complete waste of time. I have another call scheduled later today.
This will format the drive, copy the macOS installer to the drive, and make the drive bootable. This is how one installs macOS from a USB drive onto another drive. If that is what you are trying to do, then the support rep ain’t lying.
ok, I am getting myself a headache over this. For some reason it's not restoring everything. My applications are not being restored, my download folder in empty, and my non iCloud sync folders are also MIA. I am not sure what I am doing wrong. I will now do attempt #3
I tried installing macOS26 on an external with a bootable USB installer, and then migrating from the internal with Setup Assistant. Mine also didn’t migrate Applications, and maybe other things. Not sure if you were also trying to migrate from the internal? I have done other successful migrations with macOS26 from TM and CCC backups, but never directly from the internal before.
I haven’t tried again since, because I have decided not to go this route, but my advice would be to try again, and this time migrate from a TM or CCC backup of the internal, rather than directly from the internal.
When you try again, DO NOT use “Erase all data and settings” while booted from an external to get back to factory state, as it will wipe both internal and external. Use Disk Utility on Recovery or the Bootable USB to erase the volume pair on the external. Or it might work to just delete the external -Data volume which would avoid reinstalling on the external, but can’t be sure it would boot to Setup Assistant on the external.... never tried this, but nothing lost by trying.
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I don't get it. I am lost. I tried many times do get my applications and other stuff back its very annoying.
I don’t know why it happened to both of us, but did you try starting over and migrating from a backup as I suggested?
Do you mean erase everything again or just the data in disk utility? then reinstall Mac OS 26 afterwards do a migrate assistant?
Also I noticed something when doing any type of restore from backup it won't recreate your old Mac account instead it will make you use the current Mac account why?
so when you meant migrate assistant do you mean while Mac is setting up or do you mean when Mac is logged into the account?
Not sure what you mean by "just the data in Disk Utility", but I suggest you boot back to your internal, erase the external and start again as per Install macOS on an external storage device and use it as a startup disk as @Bigwaff mentioned.
I have never seen this. If you use Setup Assistant (the migration that runs on a brand new Mac first boot, or after an erase and re install, or after an "Erase all content and setting") there is no existing user so it will migrate the user(s) it finds on whatever you are migrate from. If you are using Migration Assistant from Utilities on an already setup Mac, if it finds the name already in use it will ask if you want to overwrite the existing one. If the names are different you will end up with both existing and migrated users.
As above the one that runs during set up is usually called Setup Assistant and what I use whenever possible.
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It would have been with Mojave or earlier, but since the advent of the SSV, Mike Bombich’s recommendation has been to install and use CCC as a migration source (as in what I said above), and he has relegated bootable back ups to Legacy status, because of all the problems. The migration method has worked many times for me without problem, with one exception… this last time when I tried to migrate direct from the internal, (like the OP) instead of from a TM or CCC backup. I don't know if this a bug or what…not seen other reports.
The OP could certainly try using the Legacy method with Tahoe. Start with this CCC page and the links on it. Superduper! app has a more positive approach to bootable backups (though it also uses Apple’s proprietary ASR method used by CCC) so it might be possible to create a bootable external of Tahoe with that.
I have never tried either for this purpose.
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I just repeated this and everything migrated correctly using the internal as the migration source.
So OP, maybe just try again. This is not the first time for me that a second attempt at something worked after an identical previous attempt failed. The migration on previous (failed) attempt definitely happened...I sat and watched the migration process count down, but on roboot, no Applications folder and probably not other stuff (I didn't check after I realised the migration hadn't worked properly).
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"Why can't I install Mac OS 26 onto external and boot from it?"
You can.
You just have to do it carefully.
And... even when you do it carefully, sometimes it STILL can fail on you.
I think this is the process that worked for me:
a. boot up from your existing OS (did you tell us what that is?)
b. format your external SSD to APFS, GUID partition format, and make sure case is set to INsensitive.
c. I recommend you go to Mr. Macintosh's page here to get a direct download URL:
mrmacintosh.com
d. the file (from Mr. Macintosh) will download as a pkg file. I SUGGEST that you set Safari to download this right to your dekstop.
e. double-click the package file and run the installer. THIS DOESN'T INSTALL THE OS. Instead, it places the installer app into your applications folder.
f. now launch the installer app. When it asks you WHERE to install, "point it" at the EXTERNAL drive and turn it loose.
g. the install is going to take a while, involving several reboots, firmware update, etc. One just has to be patient.
h. when done, you'll see the initial setup screen.
AT THIS POINT, you need to decide how you're going to proceed:
- do you want a completely fresh setup (new account, etc.)?
- do you want to migrate from your existing account?
- do you want something else (you mentioned "recovery" from an old MBP above)?
I'd suggest a new account.
There are "ways" to get stuff onto it and working from your older accounts.
If you want to recover stuff from the old MBP, tell us what year it was made and what OS was running on it. We need those particulars to advise further.
Again, the above process worked for me.
But I, too, had one or two "failures" before I got it right and got Tahoe running on an external SSD.
(BTW, DON'T try installing a modern Mac OS onto a platter-based HDD. It either won't work at all, or will be an awful experience...)
You can.
You just have to do it carefully.
And... even when you do it carefully, sometimes it STILL can fail on you.
I think this is the process that worked for me:
a. boot up from your existing OS (did you tell us what that is?)
b. format your external SSD to APFS, GUID partition format, and make sure case is set to INsensitive.
c. I recommend you go to Mr. Macintosh's page here to get a direct download URL:
macOS Tahoe Full Installer Database. Download Directly from Apple!
Download macOS Tahoe full installer with one click straight from Apple! Every version of Tahoe Beta & Final available all in one place!!
mrmacintosh.com
e. double-click the package file and run the installer. THIS DOESN'T INSTALL THE OS. Instead, it places the installer app into your applications folder.
f. now launch the installer app. When it asks you WHERE to install, "point it" at the EXTERNAL drive and turn it loose.
g. the install is going to take a while, involving several reboots, firmware update, etc. One just has to be patient.
h. when done, you'll see the initial setup screen.
AT THIS POINT, you need to decide how you're going to proceed:
- do you want a completely fresh setup (new account, etc.)?
- do you want to migrate from your existing account?
- do you want something else (you mentioned "recovery" from an old MBP above)?
I'd suggest a new account.
There are "ways" to get stuff onto it and working from your older accounts.
If you want to recover stuff from the old MBP, tell us what year it was made and what OS was running on it. We need those particulars to advise further.
Again, the above process worked for me.
But I, too, had one or two "failures" before I got it right and got Tahoe running on an external SSD.
(BTW, DON'T try installing a modern Mac OS onto a platter-based HDD. It either won't work at all, or will be an awful experience...)
I use CCC to clone my system disks. It still works for me in Tahoe, Beta 4 👍 And YES, they boot just fine🤗
Lou
One other thing about "recovering" your "former MBP".
I could be wrong about this, and I welcome correction from others with more knowledge than me, but...
...You can't boot an external drive containing Tahoe from the MBP unless that MBP has ALREADY BEEN UPGRADED to Tahoe and the internal drive works.
If you try, you're going to get an error that the external drive can't boot the MBP without "a software update" -- which is probably firmware.
And I don't believe you can have the firmware updated unless the MBP itself is capable of being upgraded to Tahoe (that means "recent enough").
What year was the MBP made?
Is there something wrong with it right now?
Does it boot?
If so, to which OS does it boot?
I could be wrong about this, and I welcome correction from others with more knowledge than me, but...
...You can't boot an external drive containing Tahoe from the MBP unless that MBP has ALREADY BEEN UPGRADED to Tahoe and the internal drive works.
If you try, you're going to get an error that the external drive can't boot the MBP without "a software update" -- which is probably firmware.
And I don't believe you can have the firmware updated unless the MBP itself is capable of being upgraded to Tahoe (that means "recent enough").
What year was the MBP made?
Is there something wrong with it right now?
Does it boot?
If so, to which OS does it boot?
If you install Tahoe on an external connected to a Mac which is still on Sequoia, the firmware on the internal will be updated by the installation process without any special action. So the idea of trying Tahoe on an external without affecting the internal is a myth. However Sequoia runs fine with Tahoe firmware so it doesn't matter, except that if you ever do a reinstall from Recovery, Tahoe will be installed because the firmware is Tahoe.
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Re Mike's reply 20 above...
What you described above is exactly what I did, and it works.
However... the OP seems to be saying that he wants to create the Tahoe boot drive (on Mac "a"), and then take it to another Mac (sounds like some kind of older MacBook Pro), to "recover" it.
Since the OP didn't give us much info to go on, I'm going to GUESS that either:
- The older MBP has a failed internal drive and won't boot
or
- The older MBP has an older OS (not Sequoia).
OP...
Are you still reading?
Which of the above is correct?
Or is it something else?
What you described above is exactly what I did, and it works.
However... the OP seems to be saying that he wants to create the Tahoe boot drive (on Mac "a"), and then take it to another Mac (sounds like some kind of older MacBook Pro), to "recover" it.
Since the OP didn't give us much info to go on, I'm going to GUESS that either:
- The older MBP has a failed internal drive and won't boot
or
- The older MBP has an older OS (not Sequoia).
OP...
Are you still reading?
Which of the above is correct?
Or is it something else?
Your point about getting about using a Tahoe external on Mac not already upgraded to Tahoe would certainly apply in this case, though not sure exactly what would happen.
I hadn't thought that the OP might be considering using the Tahoe external on a different Mac from the one where the external was created, but you are right that this might be what he is aiming to do. I did try this once and was surprised that it worked...I had thought with all the security hoops around Silicon Mac booting it wouldn't. In my case there was not a firmware difference and I can't recall if I had to reduce the StartUp Security settings in Recovery....I think not because I was the all important "owner' on both Macs.
Mike wrote:
"you are right that this might be what he is aiming to do. I did try this once and was surprised that it worked..."
Why I came to conclusions I posted above:
I had previously created a Tahoe boot drive on my 2021 MacBook Pro 14", which still has Sonoma 14.x installed.
The Tahoe external boot drive worked on the MBP.
BUT...
... When I tried to boot my 2014 m4 Mini using the same drive, it wouldn't do it. Instead, it gave me the alert that (best of my recollection) "a software update was required" in order to boot Tahoe.
I'm going to GUESS that this was because my Mini (at the time) had no prior "connection" to Tahoe at all. (that's changed now)
Thus, the firmware wasn't updated to the point where booting from Tahoe was possible.
That's why I posted that the OP won't be able to use the Tahoe external boot drive to boot a MBP that has had "no prior contact with" Tahoe...
"you are right that this might be what he is aiming to do. I did try this once and was surprised that it worked..."
Why I came to conclusions I posted above:
I had previously created a Tahoe boot drive on my 2021 MacBook Pro 14", which still has Sonoma 14.x installed.
The Tahoe external boot drive worked on the MBP.
BUT...
... When I tried to boot my 2014 m4 Mini using the same drive, it wouldn't do it. Instead, it gave me the alert that (best of my recollection) "a software update was required" in order to boot Tahoe.
I'm going to GUESS that this was because my Mini (at the time) had no prior "connection" to Tahoe at all. (that's changed now)
Thus, the firmware wasn't updated to the point where booting from Tahoe was possible.
That's why I posted that the OP won't be able to use the Tahoe external boot drive to boot a MBP that has had "no prior contact with" Tahoe...
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I am trying to create macOS Tahoe USB install media on a flash drive formatted GUID and Mac OS Extended Journaled named MyVolume which a senior advisor told me to do. I want to install it on my external USB named MAC an APFS volume. Also the command isn't workingDid you create macOS Tahoe USB install media onto the Samsung T7 and are trying to run the installer from the T7 in order to reinstall macOS Tahoe onto your MBP? Or are you trying to install macOS Tahoe onto the T7 and boot from the T7? It's not clear from your run on sentence.
Install macOS on an external storage device and use it as a startup disk - Apple Support
If you have an external storage device, you can set it up as a Mac startup disk.support.apple.com
sudo /Applications/Install\ macOS\ Tahoe.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume
Password:
sudo: /Applications/Install macOS Tahoe.app/Contents/Resources/createinstallmedia: command not found