Migration Assistant Failure

While Migration assistant is a no brainer, my approach with a new mac would always be to go as clean as possible.

You have a fresh install: just copy data to an external disk manually (each user profile if more than one). Typically: everything in « Documents ».

Then reinstall apps you really use : making sure you install the latest version of everything.

Then recopy data in the appropriate folder (typically « Documents ») for each user (you eould have to recreate each user profile if you had more than one and still wish to pursue same way).

May sounds a couple of hours, but likely less than the 10 you wasted, and more importantly: you will not import stuff you no longer need, corruption, and you will not crowd your new mac with stuff no longer needed or relevant.

Hope this helps,

Wi-Fi and Ethernet are slow and unreliable.

The faster, easier and most reliable way to Migrate, is from your old iMac's Time Machine backup.

see > Transfer to a new Mac with Migration Assistant - Apple Support

+1, MA is an old Apple bot, just like its equally ancient brother, Time Machine, both way past their retirement dates. Avoid them both and setup fresh. It’s easier than you think, enjoyable even.