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            macOS 26 Tahoe Won't Install on the M3 Ultra Mac Studio

   Adam Engst

   Thanks to our old friend Ken Gruberman, who [1]wrote on TidBITS Talk in
   response to '[2]When Should You Upgrade to Apple's OS 26 Releases?'
   (15 September 2025):

     If you have an M3 Ultra Mac Studio, like me, the answer is NEVER.
     That's because macOS 26 Tahoe WILL NOT INSTALL on these machines;
     you can't update the existing system nor install it onto an external
     drive.

   [3]Others are also reporting the issue on the Apple Support Community,
   so it's not an isolated problem. While some Apple support reps may not
   yet be aware of the issue, the growing number of reports suggests that
   Apple's engineers are working on a fix. In the meantime, M3 Ultra Mac
   Studio users should either stay on their current version of macOS or
   upgrade to macOS 15.7 Sequoia for the latest security fixes. Given the
   high-end nature of the affected machines and embarrassing nature of the
   lapse, I expect Apple to address this issue quickly, likely within
   days.

   [4]Read original article

References

   1. https://talk.tidbits.com/t/when-should-you-upgrade-to-apple-s-os-26-releases/31915/71?u=ace
   2. https://tidbits.com/2025/09/15/when-should-you-upgrade-to-apples-%ef%a3%bfos-26-releases/
   3. https://discussions.apple.com/thread/256136192?sortBy=rank
   4. https://talk.tidbits.com/t/when-should-you-upgrade-to-apple-s-os-26-releases/31915/71?u=ace

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