Showing a HUGE Library file in Migration Assistant!

It turns out that my problem was caused by Microsoft's OneDrive application. If there are folders on your computer that you are syncing to the Cloud using OneDrive, you have the option of saying "Free Disk Space" and have files be downloaded on-demand—only when you use them. This does indeed free disk-space. However, there is a bug: when Migration Assistant do the volume size accounting on your disk, they count the full size of files on the cloud. I believe this is due to the metadata/headers of the small place-holder files that OneDrive keeps on your computer for the on-demand files on the cloud. Interestingly, the Disk Utility and the "**" command do not make this mistake (ostensibly because they don't count size file-by-file or calculate actual file size on disk).

Anways, you have several solutions in this case. One is to unlink your old mac from OneDrive, migrate, and then re-link. Another is to unselect the large on-demand folders in OneDrive "Manage Storage" before migration and re-select afterwards.

I suspect this problem could be similarly caused by other cloud-storage apps from Google or Dropbox when you choose any kind of "download on demand" option.

I hope apple addresses this issue by altering their Migration Assistant settings.

Hi skypanda47,

We see when trying to transfer data via Migration Assistant from one Mac to another, you're getting an extremely large file size.

To start, there is a later patch for macOS Monterey, we'd recommend updating both devices to it:

• Update macOS on Mac

After updating, try Migration Assistant again. If you still receive the larger file size, let us know.

Take care.

Hi Skypanda47,

Thanks for the heads up.

I gave in too, and took the slow route using my Timemachine backup (via a Synology NAS).

Looking up the available backups: 1h

Calculating the size of the selected backup: 1h

Migrating the backup to my MacBook: ~6h

So not as fast as the direct copy from Macbook to Macbook (I did one a week ago that took me less than 1h).

But at least this option was successful.

I'm having the same issue as skypanda47 and I've updated the software of both Macs. The hard drive of my old MacBook Air is 250GB but Migration Assistant shows a Library folder of over 700GB which obviously isn't possible. My new MacBook Air hard drive is 500GB so there should be no issue with file size.

I am trying to migrate my account between two devices with the very latest version of Monterey (12.3), and on my source device with a 512GB SSD I am told that I have 3.2TB in my ~/Library folder, which quite clearly cannot be true.

Is there no fix for this bug?

I continue to have this issue even after updating to 12.3. Migration assistant thinks my /library folder is larger than my hard drive. This is preventing me from sending my MacBookPro for repair.

The same for me. Is there any solution? 500GB SSD gives 1,5T Library size

Same problem here.

2016 MBP to new M1

updated OS on both machines

I’m seeing a 800TB library folder on migration assistant…

crazy.

really annoying I can’t get I to my new machine!!!