Can't install MacOs Tahoe on Mac Studio M3 Ultra

The panic you’re seeing:

ANEHWDevice::Failed to validate ANE register offset 0x5a8...

…means the installer is loading the new Tahoe kernel/driver for the Apple Neural Engine, but the hardware check fails.

This can happen if:

• The Tahoe build you’re getting has a driver mismatch for your exact M3 Ultra revision.
• There’s a firmware update bundled in Tahoe that isn’t applying correctly during the install phase.
• A known launch-week bug in Tahoe 26.0 is affecting certain Apple Silicon Macs.

Steps to Try:

Here’s a sequence that’s worked for similar cases:

(1) Check for a Newer Build of Tahoe

Sometimes Apple silently reissues the same version with a fixed build number.

In Terminal:

bash
softwareupdate --fetch-full-installer --full-installer-version 26.0

Then check the build number in About This Mac → System Report → Software after download (before install). If it’s newer than your current installer, try again.

(2) Install via macOS Recovery

Shut down your Mac.

Hold Power until “Options” appears.

Choose Options → Reinstall macOS.

This pulls the latest signed installer directly from Apple’s servers and bypasses some of the live-update process that’s triggering the ANE panic.

(3) Try Safe Mode Install

Boot into Safe Mode (hold Shift after selecting your startup disk in the boot picker).

Then run the Tahoe installer from there — this can prevent certain kernel extensions from loading during the upgrade.

Erase-Install on an External Drive (Non-destructive test)

Use a spare SSD, format it APFS, and install Tahoe cleanly to it.

If it boots fine, the issue is with the in-place upgrade path; if it still panics, it’s a firmware/driver bug.

(4) Escalate to Apple

Given the ANE-specific panic, this is likely something Apple needs to patch.

File a Bug Report here for your specific Mac model: Product Feedback - Apple

My Take

This isn’t a storage, network, or generic corruption problem — it’s almost certainly a Tahoe 26.0 + M3 Ultra ANE driver issue. Until Apple pushes a fixed build, your best bet is either: Install via Recovery (which sometimes pulls a patched build), or wait for 26.0.1 or a supplemental update.

ckh1272 wrote:

DFU is only for firmware revives or restore. OS installation is not an option that way.

A DFU Firmware Revive will reset the security enclave and system firmware. This should be updating the system firmware to the most recent firmware available which right now should be the macOS 26.0 related firmware.

A DFU Firmware Restore will do the same thing as the Revive, but will also reset the internal SSD and it will also push a clean copy of macOS onto the internal SSD. I don't know which version of macOS will be pushed onto the internal SSD with this process (I never really paid attention to it). I think it may be possible to use Apple Configurator 2 to push a specific version of macOS onto the internal SSD, but I'm not sure how that can be acquired.

Unfortunately a DFU Firmware Revive or Restore does require access to another Mac running macOS 26 Tahoe, or possibly for a little while macOS 15.x Sequoia may work as well with the latter perhaps requiring the use of Apple Configurator 2 (hopefully you already have the version compatible with Sequoia).

Here is an Apple article with instructions:

How to revive or restore Mac firmware - Apple Support

Something else must have been done, namely updated firmware (another user posted that is what an Apple Store did for them) before they upgraded you to Tahoe.

That is exactly what the DFU Firmware Revive or Restore process does. It reflashes the system firmware. Another user in this thread or another similar thread on this forum actually stated quite clearly the Apple tech performed a DFU Firmware Revive or Restore.

I can understand that post may have been missed by many people due to the horrible way posts are ordered on this forum with the default "Ranked" sort method. I would recommend people to change their forum profile to set the default sort order to "Oldest" or "Newest" as the posts will be ordered in actual time order. It is possible to change the sort order for only a single thread by looking at the lower right of the initial post (or just below the "Top-ranking reply") where there is a "Sort By" option with a drop down list box.

SilverHorizonX wrote:

Can a firmware update be done remotely, or do we all need to go to the Apple Store?

If not, I am thinking of returning this M3 Ultra 96Gb for a M4 Max 128Gb

If you have access to another Mac running macOS 26 Tahoe, or perhaps even macOS 15.x Sequoia, then you can try performing a DFU Firmware Revive yourself. If you personally don't have another Mac, then how about another family member, friend, or co-worker. If your employer has an IT team and supports Macs, then they may be able to assist you. Theoretically it may be possible to use a Mac on display at an Apple Store for this process (I have never been to one so I don't know what is allowed).

I'm not sure if a DFU Firmware Revive is sufficient or whether it may require the more drastic DFU Firmware Restore which will reset the internal SSD destroying all data on the internal SSD & push a clean copy of macOS onto the internal SSD.

I would think a DFU Firmware Revive should be sufficient, but Apple isn't good at providing lots of details about either process.

Unfortunately a DFU Firmware Revive or Restore does require access to another Mac running macOS 26 Tahoe, or possibly for a little while macOS 15.x Sequoia may work as well with the latter perhaps requiring the use of Apple Configurator 2 (hopefully you already have the version compatible with Sequoia).

Here is an Apple article with instructions:

How to revive or restore Mac firmware - Apple Support

Make sure you have a good backup of your computer before you do anything...including trying to install the macOS 26 Tahoe upgrade. There are a lot more new ways to permanently lose access to the data on the internal SSD of the recent Macs due to all of the hardware, software, and security changes.

I encountered the exact same issue on my Mac Studio M3 Ultra.

I decided to take it to the Apple Store to have them upgrade it, just in case the build they have available in the store is different.

To my surprise, they were able to install Tahoe on the first attempt. The store employee informed me that their flashing process also upgrades the firmware of several components.

Well as I said on a previous post, I took my Mac Studio M3 Ultra to the Apple Store and had them update it.

They were able to install 25A354. I don't think it's the build version that is the issue, but rather a firmware update they need to ship OTA before an attempt to upgrade to Tahoe.

Taking it to the Apple Store, they were able to push firmware updates, before installing 25A354

I also had this issue. Talked this morning with an engineer, and that one said it is on the radar. Also I mentioned this thread and particular that reply that you could bring you device to an apple store to fix it. He said we could do that also at home if you have another Apple device that is non-intel. Because I have also a Macbook Pro M4 Max it was easy for me. He shared:

How to revive or restore Mac firmware - Apple Support

How to identify the DFU port on Mac - Apple Support

Hope that this helps anyone. I am now running Tahoe 26

Performed the DFU restore yesterday without issues so now I have Tahoe 26. Made a new and complete Time Machine backup right before the restore. But after running the migration assistent I noticed that none of my files had been transferred. Although the migration process appeared to work normally and went through all 1,5 million files none were actually transferred. No apps, no settings, no documents although they are included and visible in the backup. Tried three times but no files were transferred.

Could it be some mismatch between my user account and my files? Permissions problem?

Talked to a Sr Apple support person who was as confused as I.

Yes, I could have stayed on 15,7 but since I had already successfully and updated iPhone, iPad and MacBook Pro to 26 without any issues I decided to do the DFU restore. That there would be problems with migration wasn't on my radar. I just expected it to work.

Any ideas/suggestions?

Drove an hour (round trip) to the Apple Store today after making an appointment with the "Genius Bar." Told the guy my issue. He claimed that they have heard nothing about it yet. I suggested that he try installing Tahoe for me using DFU mode . . . and sure enough, it worked! Took about an hour in-store.

After he saw that I wasn't full of crap, he said that he looked online again and was seeing "a few mentions" of the issue. I told him that there were more than just a "few."

So anyhow, if you don't want to wait for an official bug fix, you can always try an Apple Store if you have one nearby.

Hello All. Thanks so much for the hint with the DFU. After having a call open with Apple support since Tuesday, tried every approach described in this forum so far - even willing to erase the disk and start from scratch, finally after trying the DFU approach this morning from a MacBook Pro to a MacStudio Ultra 3 it worked. You do not need to prepare a USB stick for that, all is done through the USB cable. I am writing from my Tahoe 26 MacStudio right now. Again thanks for this information, I did not wanted to wait any longer for a fix. So if you are willing to start fresh - this is the way.

Sorry forgot to mention. I went straight for "DFU Firmware Restore" as I did not want to waste anymore time. Since I erased the SSD before anyway I thought this is the best way and it worked great. Currently reinstalling and configuring everything...

I believe the issue what we see is that the ANE is not properly initialized and that is what my error log said. But "DFU Firmware Restore" fixed it for me it was really fast. Time Machine was taking really hours ;-). But eventually brought me Tahoe 26 with all my data and apps in it. In the current logs I don't see the ANE panic anymore, and I believe the firmware is updated. Also I used a Thunderbolt 5 cable to restore it that works perfectly.

After I tipped him off to this situation, the ever-reliable Howard Oakley of Eclectic Light figured out the Tahoe install problem: the installer, as it currently exists, does not install key system kexts / extensions causing the Apple Neural Engine to fail. Fortunately, when the installer also fails, it reverts back to what was there before so the user doesn't have a bricked machine — a small consolation. Apparently Apple simply forgot to include them in the Tahoe installer! What an embarrassing oversight. You can read Howard's report here.

There is nothing any of us can do about this other than wait for a fix; most likely it will come with 26.1 in a couple of weeks. *sigh*

Looks like macOS 26.0.1 just released with fixes for M3 Ultra Studios. It's downloading now, but I guess that should solve this for most people.

I have the exact same Mac Studio M3 Ultra with same problem. I have an open case with Apple advanced support and provided logs last night. I am running Sequoia 15.7 btw. Multiple attempts via software update, using the Full installer, safe mode update, recovery mode update, etc all result in same problem. After a normal looking 15 minute install process you boot back into Sequoia as if nothing happened with no error messages.

Would recommend opening a case as well must be something particular to this machine type.

Hey guys,

So same here, been trying all night (Paris) and all day too. Update worked flawlessly on MacBook Pro M3, and failed every time on Mac Studio M3Ultra.

I discovered one thing though : The build on my MacBook is the 25A354 (so the latest one, out yesterday) ; I uploaded through Settings/Software Update.

As I was looking for a different course of action, I used fetch In terminal to get the latest build and it doesn't matter how I much I try, I only get the RC Build 25A353. I've tried a bunch of ways of getting it, and it's always the same result, I can't seem to get the latest build.

I tried downloading it from my MacBookPro to make a USB : it's the same. I've tried maybe 5 or 6 different sources, I always end up with the exact same file. (I checked in terminal the catalog : the right build shows up in the list, but when I download it : nothing) I thought this might be Apple's CDN but how can it explain the right build showing on my other Mac, downloaded at 5 minutes intervals, from the exact same internet connection ? (I would also like to mention : I don't use VPNs so that just my normal internet access)

Maybe I'm overreaching but : If the latest build isn't really downloading, and the RC shows up in place, maybe that's why we get an error ? I mean, is there any way the ANE validation fails because there's a build conflict ? Has any of you tried the 25A354 on Mac Studio M3 Ultra and failed in the same way ? Is there any certified way to "force" a build download ?

It's just an upgrade, yes, but I think we would all agree that with this kind of money, (since it's only concerning the Mac studio M3Ultra) we should have a patch right now....