How can I fix the macOS Tahoe installation issue on my Mac Studio?

M3 Ultra Studio 2025 : Same issue. 2 hours with support on the phone last night and ultimately never got Tahoe to install. Had to wipe the machine and reinstall Sequoia from a TM backup due to system bloat sucking up half my SSD storage, presumably from the various safe mode / reinstall / migration attempts. The crash log from the kernel panic stated: panic(cpu 8 caller 0xfffffe003af90b08): "ANEHWDevice::Failed to validate ANE register offset 0x5a8 with expected value: 0x100000ff, read register value 0\n" @ANERegisterControl.cpp:177

It appears to be an issue with the Apple Neural Engine register, whatever that is.

Support tech indicated that Apple is aware and collecting information. No known fix as of last night.

BoggyBumblebee wrote:

I have the same issue; Mac Studio M3 Ultra (one day old) with 256GB Memory and 16TB SSD running Sequoia 15.7, goes through the motions of the upgrade, and then restarts back into 15.7. I've attempted this 5 times, and the third time came up with an error log dialog that I forwarded onto Apple, the other four attempts, nothing came up.

There is an obvious issue with Mac Studio M3 Ultra— and issues to upgrade. The reports are piling up.

You may well have to wait for the patch. I would not beat my head against the wall.

To be proactive you can file a bug report / submit your Apple Feedback here: Product Feedback - Apple

julienfromhouplines wrote:

Unable to install macOS Tahoe on Mac Studio M3 Ultra: macOS 26 downloads successfully (approximately 14.52GB). The 30-minute preparation time usually takes 15 minutes. Installation takes about 11 minutes.

BUT the Mac restarts after installation on Sequoia 15.2.

I tried in Safe Mode, but the same result.

I need your help.

re: macOS 26

reference the following—

Update macOS on Mac - Apple Support

If an error occurred while updating or installing macOS - Apple Support

The current stable release of Sequoia including bug fixes, security updates is macOS 15.7 - you could try that first(?)

Keep your Mac up to date - Apple Support

Keep your Mac up to date - Apple Support

OP wrote " BUT the Mac restarts after installation on Sequoia 15.2. "

That was released Dec 11, 2024 macOS 15.2 ( 24C101 )

You may consider updating the exiting Sequoia to something newer and before upGrading to Tahoe

As was also suggested by my colleague @leroydouglas

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.

Having upGraded a M2 Desktop, M4 Desktop and a M4 Laptop from Sequoia 15.6.1 directly to macOS 26 Tahoe without issues

Yes, your issue would seem localized and unique to this machine

Though, the Author has denoted, they are running a very outdated version of Sequoia dating back to Dec 11, 2024 macOS 15.2 ( 24C101 )

I agree believe this is machine specific - have done upgrades fine on M4 iMac, MacBook Air, and a M1 MacBook Air. In another post user captured a panic updating ANE (Apple Neural Engine) that may provide some insight. Add that post to my Apple Case.

I have the intel MacBook Pro 16” 2019 which has similar problems

The Mac couldn’t also install the sequoia 15.7 and when I chatted the Apple support, they advised me to put the MacBook Pro in safe mode or safeboot and then try the installation again while in that mode.

That’s what I am doing now

Hopefully it will work, then I will share with you if it works

I have the same issue; Mac Studio M3 Ultra (one day old) with 256GB Memory and 16TB SSD running Sequoia 15.7, goes through the motions of the upgrade, and then restarts back into 15.7. I've attempted this 5 times, and the third time came up with an error log dialog that I forwarded onto Apple, the other four attempts, nothing came up.

I have a M3 Ultra Mac Studio and am having the exact same issue. I was able to update to 15.7, but cannot update to Tahoe. As you stated: it goes through the entire update process and then reboots into Sequoia. I too have tried updating through software update, terminal, and downloaded package, and nothing works.

Yes I have read that posting also

Yes, same experience, but I have TONS of room & RAM. Support told me it's an issue they are aware of - and update is likely VERY imminent...