Migration Assistant stuck at 'Setting Up...' on my MacBook Pro

bentStaple wrote:

I have a MacBook Pro running a clean install of Monterey, and I'm trying to use the Migration Assistant to bring back a ton of needed files from an older Time Machine backup. I think this backup was made with the El Capitan version of MacOS, but it was in fact made on this same MacBook.

The Migration Assistant starts up, and shows a screen saying, "Setting up...", and then nothing happens for over 8 hours. It uses an older hard drive, so I would hear if it was reading/writing, but it's not.

Surely the version of Migration Assistant that comes with Monterey is backwards compatible with back-ups made on an earlier version of MacOS?

[Re-Titled by Moderator]

Restore your Mac from a backup

Restore your Mac from a backup - Apple Support

ref: If you can't back up or restore your Mac using Time Machine - Apple Support