iMac: Migration Assistant stuck via Thunderbolt

Trying to use Migration Assistant, between an older iMac and recent purchase. It gets hung at he point shown in the image. I have tried this several times, waited hours, and we get stuck here. Thunderbolt connection, and I followed the method outlined by Apple. Unning Catalina on both machines. 2014 27" model and 2019 27" refurb.


Thoughts...?

iMac 27″, macOS 10.15

Posted on Jan 2, 2026 2:48 PM

Reply
Question marked as Top-ranking reply

Posted on Jan 2, 2026 8:46 PM

The easiest and most reliable method of migrating from an old Mac to a new Mac is to simply connect the old Mac's Time Machine External Hard Disk to the new Mac and then startup Migration Assistant (Applications - Utilities - Migration Assistant) and follow the on-screen instructions. If your old Mac does not have a Time Machine External Hard Disk backup, then make one. ALL other methods may or may not work as you are discovering!!!!!

2 replies
Question marked as Top-ranking reply

Jan 2, 2026 8:46 PM in response to Charles Hess

The easiest and most reliable method of migrating from an old Mac to a new Mac is to simply connect the old Mac's Time Machine External Hard Disk to the new Mac and then startup Migration Assistant (Applications - Utilities - Migration Assistant) and follow the on-screen instructions. If your old Mac does not have a Time Machine External Hard Disk backup, then make one. ALL other methods may or may not work as you are discovering!!!!!

Jan 2, 2026 5:06 PM in response to Charles Hess

Hey there -


I have tried this several times, waited hours, and we get stuck here. Thunderbolt connection, and I followed the method outlined by Apple. Unning Catalina on both machines. 2014 27" model and 2019 27" refurb.

When you've tried this several times, has your new 2019 iMac been fully setup, or, are you running Migration Assistant during the initial Setup Assistant phase? Do you have a Time Machine backup of your old Mac on an external storage device?


Since you're using Thunderbolt, you may also be able to use target disk mode to transfer your files between your 2 Macs:


Transfer files between two Mac computers using target disk mode - Apple Support


-Jack

iMac: Migration Assistant stuck via Thunderbolt

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.