Cannot eject Time Machine drive from MacBook Pro

For the better part of the past week, I have been unable to eject my Time Machine drive. Every time I try from the finder, I'm presented with the following:

I use Jettison, and that can't eject it either:

I don't know why this problem, suddenly, developed. No applications are open and nothing is using the disk.

I have tried both of the following:

Restarting the finder.
Logging out and logging back in.

Neither is permitting ejection.

I tried to run First Aid on the volume in Disk Utility, but that won't work because the disk can't be unmounted.

Force ejecting the drive is the only thing that works.

How can I figure out what is, persistently, preventing this disk from being ejected?

My machine is a 2023 16-inch MacBook Pro running the current build of Tahoe (26.4).

[Edited by Moderator]

MacBook Pro 16″

Posted on Apr 7, 2026 8:53 PM

Top-ranking reply

Cerebro Author

Level 3

632 points

Posted on May 1, 2026 3:35 PM

Okay. I think I, finally, solved my problem. After still having issues with my TM drive failing to eject because it was "busy" (Busy doing what?), I wondered it this might be connected to another frequent issue I've been having, recently, where TM backups were failing because it claimed that my disk was "no longer encrypted":

This was a surprise to me, because I didn't remember encrypting it in the first place. Going into settings told me:

Removing my TM drive and, then, re-adding it would fix the problem. But, only temporarily.

I did some research on this and learned of one thing, unbeknownst to me, that Tahoe changed. Tahoe enabled FileVault by default. Prior to Tahoe, I did not have this enabled. Since my internal drive was, now, encrypted and my TM volume was not, this led to frequent conflicts. It seems there are two solutions:

Turn off FileVault on my internal drive.
Reformat my TM volume with encryption.

I chose the second one. Now, I haven't seen any errors all week with, either failed disk ejections, or failed back-ups. Hopefully, I'm good to go, now.

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47 replies

chesleyn

Level 1

9 points

Jun 3, 2026 12:27 PM in response to Lauraald4

Jun 15, 2026 4:42 PM in response to bagelmonkey

Alas, didn't work for me. :-(

Cannot eject Time Machine drive from MacBook Pro