John Macdonald2 wrote:
A follow up. . . I see I already have Migration Assistant in the Applications Utilities folder. So it looks like it's not going to work as advertised. And I'm not nearly computer savvy enough to created a bootable disc. Am I stuck with Sonoma, in which everything processes at the speed of a crippled snail?
https://discussions.apple.com/content/attachment/164b11a8-fcb1-4034-bb85-50d907985323
Clicking "Install macOS" simply takes me back to the Recovery utilities screen.
Predicated on the User byline " iMac 27″, macOS 14.4 "
This appears to an Apple Intel Computer ?
Time Machine sadly does not contain a full and working copy of the Operating System
That stop somewhere around macOS 11 Big Sur
TM Backup does contain all this was in the User Folder ( Home Folder ) of this computers
To Downgrade is possible but will require creating a Bootable Installer of the previous version of macOS
I suggest a a Bootable Installer as it is better to have the Operating System Media on bootable installer disk rather than deepening on Internet Recovery Mode
Scorched Earth Method
This method will WIPE ALL Data and there is No DATA Recovery - Period.
>> Only works on Intel Based Apple Computer <<
To perform this action will require booting from a Bootable Installer.
The Bootable Installer can Only be performed on an Apple Computer
This will have to be performed from a Qualifying Computer to run the version of macOS to be made on the Bootable Installer. Example : Bootable Installer of Big Sur would have to be done on a computer that Qualifies to run Big Sur.
Notation: If the computer being used to perform this action is Too New or Too Old to qualify to run the version of macOS - this computer can’t be used.
Alternative is, to gain access to a Qualifying Apple Computer from a family member, friend or associate.
Shutdown computer and disconnect all external drive Except the newly created Bootable Installer.
Restart and immediately hold the OPTION key until the Startup Manager appears and choose the USB Drive.
It will present options >> Disk Utilities >> View >> View ALL attached Drives.
Choose the Upper Most Drive ( not the volumes indented and list below ).
The drive normally is called Apple Media or Apple SSD - that is the drive to Erase and format as APFS with the GUID Partition Map. This applies to macOS 10.14 Mojave and above.
Once that is done >> backup out of Disk Utilities and choose install macOS.
Follow the prompts and it may automatically reboot several time.
Upon a final reboot - Setup Assist will present with the newer version of macOS.
You can use Setup Asset and point it to the Time Machine Backup Drive. This is a One Time offer. Thereafter you will need to use Migration Assist