Apple’s macOS 26 Tahoe rolled out on September 15, promising performance gains and new features for Apple Silicon Macs.

However, some Mac Studio owners running the M3 Ultra chip report that their machines are failing to complete the installation and reverting to macOS Sequoia.

While the reports are not widespread or officially confirmed, Tahoe installation problems have been noted across multiple Macs.

Common causes include insufficient storage, corrupted installers, or unstable connections.

Apple’s own guidance advises updating via macOS Recovery, checking free disk space, and ensuring a reliable internet link.

The Mac Studio is marketed as Apple’s ultimate desktop for creative professionals, which makes even isolated hiccups embarrassing for the company.

While there’s yet to be official confirmation of an issue, it appears there definitely is one

There is a precedent for this type of issue.

Some M3 Ultra–equipped Studios were unable to install a release candidate of macOS Sequoia earlier this year due to missing decryption keys on Apple’s servers.

That highlighted the risk of firmware–software mismatches in early builds.

So far, Apple has not publicly confirmed any rollback bug tied specifically to Tahoe on M3 Ultra hardware, nor commented on speculation around the Apple Neural Engine.

Until the company issues a fix or statement, the claims remain unverified.

For now, Mac Studio owners who rely on stability may want to hold off on upgrading, keep backups in place, and monitor Apple’s support pages for updates.

For even in Apple’s tightly controlled ecosystem, the occasional software roadblock can still trip up its most powerful hardware.