Tahoe update bricked my Mac Studio, stuck in DFU, probable RecoveryOS corruption

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Level 1

4 points

Tahoe update bricked my Mac Studio, stuck in DFU, probable RecoveryOS corruption

My M1 Ultra Mac Studio became a brick when I updated from macOS Tahoe 26.0.1 to 26.1. I have no idea what happened. I hit the update/restart button, walked away, and came back to a Mac that wouldn't start.

I determined the system was in DFU mode and attempted "Revive" many times, from two different host macs and with multiple apple-issued USB-C cables. I know I am plugged into the correct DFU port on the Mac (rightmost on back, next to the Ethernet port). Revive always fails immediately after the LED switches from amber to white, when Apple Configurator/Finder says "Waiting for Mac". The failure is error 102. I finally tried "Restore" with the understanding that I would be able to "Share Disk" after the

From my research, I believe what's happened is that (a) firmware is being transferred/loaded successfully as part of revive/restore; (2) at the moment the LED switches, the system tries to boot RecoveryOS, but this is failing, presumably because the RecoveryOS volume is corrupted.

I have spoken to Apple reps at the store and one senior advisor on the phone, but none of them seemed to really understand the issue here-- it was all just "well we can try to run a revive/restore" or "we can replace your logic board" or something. Does anyone here have any expertise or suggestion? I need to retrieve the data volume if at all possible and also get my mac to actually boot again.

Mac Studio, macOS 26.0

Posted on Nov 20, 2025 11:55 AM

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Answer 1

HWTech

Level 9

68,222 points

Nov 20, 2025 7:19 PM in response to horsecandy

horsecandy wrote:

I finally tried "Restore" with the understanding that I would be able to "Share Disk" after the

A DFU Firmware Restore will destroy all data on the internal SSD. See the following Apple article for instructions & details:

How to revive or restore Mac firmware - Apple Support

From my research, I believe what's happened is that (a) firmware is being transferred/loaded successfully as part of revive/restore; (2) at the moment the LED switches, the system tries to boot RecoveryOS, but this is failing, presumably because the RecoveryOS volume is corrupted.

If the Mac is booting into Recovery Mode or Activation Mode when performing a DFU Firmware Restore, then the internal SSD has most likely already been reset and the data is permanently gone.

I have spoken to Apple reps at the store and one senior advisor on the phone, but none of them seemed to really understand the issue here-- it was all just "well we can try to run a revive/restore" or "we can replace your logic board" or something.

Nobody understands DFU Firmware Revive & Restore beyond what Apple has posted in the Apple article I linked. Apple techs don't know anymore than the information in that article. Apple has designed these recent Macs to be very difficult to troubleshoot, restore, and repair.

Does anyone here have any expertise or suggestion?

Yes, I have a good bit of experience supporting my organization's Macs. They are still a huge mystery since there is very little technical details about them and very few options for troubleshooting the M-series Macs compared with the 2015 & earlier models. It is very difficult to troubleshoot & repair them.

Suggestions: Make sure you have frequent & regular backups of your computer and all external media (including the cloud) which contains important & unique data. There are a lot more new ways to permanently lose access to the data stored on the internal SSD of the recent Macs due to all of the hardware, software, and security changes.

Back up your Mac with Time Machine - Apple Support

I need to retrieve the data volume if at all possible and also get my mac to actually boot again.

I think your data may already gone. You would need to contact a professional data recovery service to see if they can access your data. It will likely be very expensive. See if you can boot into Target Disk Mode....this is your most likely option to access the data if it still exists. See the following Apple article for instructions:

Use macOS Recovery on a Mac with Apple silicon - Apple Support

If a DFU Firmware Restore is unable to complete successfully, then you have no hope of getting the Mac to boot again unless you have Apple or an AASP repair the Mac.

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Answer 2

Nov 20, 2025 2:25 PM in response to horsecandy

<< Does anyone here have any expertise or suggestion? >>

Yes.

The people you have been talking to have already made the best suggestions possible. I am sorry you did not like their answers, but there are no substantial other answers.

I am most deeply sorry that you may have to learn the hard way that the files on modern computer are so very transitory, and may disappear without warning.

Apple provides the free Utility, Time Machine, and urges to to make backups of your files at every turn.

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Answer 3

Nov 22, 2025 12:38 PM in response to horsecandy

It will be very interesting to hear whether/what DriveSavers is ultimately able to save, and at about what cost.

Please keep Readers posted.

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Answer 4

horsecandy Author

Level 1

4 points

Nov 22, 2025 5:34 AM in response to HWTech

Thanks HWTech for this useful answer. I realize my previous understanding of "Restore" was wrong and it's good context to hear that even experienced techs like yourself are in the dark about a lot of M-series Mac issues due to low info availability.

FWIW, after a long troubleshooting session with ChatGPT about this (which was weak in its ability to cite sources), my current assessment of the likely situation is:

My SSD was too full when I launched the update.
This caused the update to fail and put the machine into DFU.
While the bootchain and recoveryOS are successfully sent from the host and loaded to RAM during DFU revive/restore, RecoveryOS fails to boot because of a logic board failure.
The logic board failure was not caused by the update. It is unclear how long it has been an issue, but it is only exposed/fatal in DFU mode because hardware is utilized differently than in normal operation.
Though I have tried both revive and restore, they both fail at the same time (waiting for USB handshake after RecoveryOS boot) before any writing to the SSD is done.
Since this is a logic board failure rather than data corruption, my data is intact but inaccessible by regular means.
The data can be recovered using special hardware tools that mitigate the board failure to allow a boot.
Apple does not offer these services, but third parties (very expensive...) do.

I sent the machine to Drive Savers (https://drivesaversdatarecovery.com/) data recovery service. My conversation with the Drive Savers intake guy was much more enlightening and confidence-inspiring than any of my conversations with the Apple techs I spoke to. I'm sure there are plenty of very helpful and knowledgable Apple Techs, but it's really a roll of the dice who you get, and certainly in this case they did not do a good job of routing me to someone knowledgable about my specific issue.

For anyone else in a similar boat, Grant Bennet-Alder above was flat wrong when he confidently assured me I had already received "the best answers possible" from Apple. It is entirely possible that, like me, you will have a better chance of effectively troubleshooting and diagnosing a machine in this situation with Drive Savers (or another third party service) than Apple.

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