Many users see the same loop: the update prepares, reboots, counts down to “Less than a minute,” then dumps you back into Sequoia with an “unexpected reboot” message.
The logs point to the culprit:
panic(cpu 8 caller 0xfffffe0050ee4b08):
"ANEHWDevice::Failed to validate ANE register offset 0x5a8…"
That line means the Tahoe installer is trying to load a new kernel extension for the Apple Neural Engine (ANE), but the validation check fails. In plain English: Tahoe’s ANE driver doesn’t play nice with your exact M3 Ultra revision.
Table of contents
Why this happens
- Driver mismatch: The initial macOS Tahoe 26.0 build may not fully support all M3 Ultra revisions.
- Firmware hiccup: Tahoe includes ANE firmware updates, but they may not apply correctly during install.
- Launch-week bug: Like iOS 26, new macOS releases often ship with quirks that Apple quietly fixes with reissued builds.
What you can try
1. Fetch a fresh build
Apple sometimes reissues the same version with a different build. Run:
softwareupdate --fetch-full-installer --full-installer-version 26.0
After download, check the build number in Apple menu → About This Mac → System Report → Software. If it’s newer than what you tried, run the installer again.
2. Install via macOS Recovery
A Recovery install pulls the latest signed image directly from Apple.
- Shut down your Mac.
- Hold Power until Options appears.
- Pick Options → Reinstall macOS.
This bypasses some of the live-update process that can trigger ANE panics.
For more detail, see our Tahoe install troubleshooting guide.
3. Try Safe Mode
Boot into Safe Mode: restart, then hold Shift after selecting your startup disk.
Run the Tahoe installer there. Safe Mode loads fewer kernel extensions, which sometimes avoids the crash.
4. Test on an external drive
If you have a spare SSD:
- Format it APFS.
- Install Tahoe cleanly.
If it boots fine, the in-place upgrade path is the issue. If it still panics, you’re looking at a firmware/driver bug.
5. Report to Apple
This is almost certainly an ANE driver problem, not storage or user error. File a report with logs via Apple Feedback.
Until Apple ships a patched build, likely as macOS 26.0.1 or a supplemental update, your best bet is a Recovery reinstall or staying on Sequoia 15.7 if your Mac Studio is production-critical.
If you’re curious about how Tahoe compares across platforms, check out our breakdown of macOS Tahoe vs Windows 11, or dive into what’s new in iPadOS 26 and watchOS 26.
For day-to-day tips, see how to use Clipboard History in Tahoe or even move Safari’s search bar on iPhone if you’re updating across devices.
