I purchased a new MacBook Pro. My old one is a MacBook Pro mid 2012 running macOS Catalina 10.15.7 my new MacBook Pro macOS Big Sur 11.2.3 I am trying to run migration assistance without success. It keep searching and nothing happens.

JMC1959 wrote:

Both operating systems need to be the same for migration assistant to work properly. I just went through this last week upgrading to a new MacBook Pro.

This is absolutely incorrect. I have migrated successfully from older systems to newer ones with Migration Assistant at least 20 times over the years. https://support.apple.com/en-us/HT204350 Some older Macs cannot be upgraded past an older OS yet they are migrated successfully every day to Big Sur by Apple users or by Apple employees in the Apple Store.

Move your content to a new Mac

What method are you using via Wifi, Time Machine Backup ?

Ok - just a suggestion. Would not Migrate any Applications as many might or might Not work on the New Apple Silicon M1. Would be inclined to move most other things and Install Applications fresh. Best also to verify with Catalina Applications if they have update / upgrades making them Compatible with Big Sur and M1 CPU

If you are continuing to have issues when connecting the Macs directly with a cable, you can alternatively make a Time Machine backup and then connect that to the new Mac and migration assistant will work with that backup to migrate from.

This method also works with other types of backups, such as those made by Carbon Copy Cloner or SuperDuper cloning programs.

Harriet Christakos wrote:

DON'T DO IT! Big Sur is nothing but trouble. First, your printer won't work and Apple does/has done nothing to fix it. Stick with Catalina.

This is not helpful advice because the new Mac comes with Big Sur, you cannot use Catalina on a new Mac that came with Big Sur. Big Sur is the only option.

For the original poster, P. Phillips had good suggestions earlier to not migrate applications and third party software as some may not run properly on the new M1 Mac. Better to install software from scratch (ok to migrate just user files).

Since you have already done this now, it's too late, but you can run a utility called Etrecheck and post the results here. Best to run it with access to the entire computer, which you have to grant. Post the results from Etrecheck using the button below that looks like a sheet of paper with a corner folded. Etrecheck may help people reading this to identify the application or extension that you brought over that is causing the issue. Examples of possibly problematic software include anti-virus, software to "clean" your computer, security software etc.

This is very helpful. Thank you. I'm helping someone else do the same thing, but her mid-2012 MacBookPro now has High Sierra. Should I recommend that she first upgrade to Catalina, then backup her old MBP before running Migration Assistant?

I'm concerned because I went through this process myself last summer. I was starting with a 2011 iMac running El Capitan and transferring data to a new MBP with Catalina. I had many problems -- had to erase the new MBP and start from scratch two or three times. I ended up believing that part or most of the problem was that the Migration Assistants in the two systems were just too far apart to work properly.

Thanks for any advice.

Again, for Migration Assistant, a fairly reliable method is to make a Time Machine (or clone-type) backup on an external drive. Then run Migration Assistant on the new Mac and when prompted, connect the backup drive to it and tell it to migrate only the user account(s) and files, nothing else (no settings, no applications ...). You never have to connect the two computers or run programs on both together.

I recently did this on a new Mac running Catalina, migrating from one on High Sierra. Worked very smoothly. High Sierra is more recent than El Capitan, of course, but migrating only files should work fine. Install applications anew on the new Mac, being careful to use only the latest installers, check online first before each install for compatibility with the later MacOS, and avoiding installing any anti-virus, security packages, or "cleaner" programs.

Ah now that is Great News - The Thunderbolt cable Solve your issue.

Very Welcome and Thank you too for keeping us updated on your success.

DON'T DO IT! Big Sur is nothing but trouble. First, your printer won't work and Apple does/has done nothing to fix it. Stick with Catalina.

Both operating systems need to be the same for migration assistant to work properly. I just went through this last week upgrading to a new MacBook Pro.