Upgraded to macOS 27 and something broke? Start here.

Apple released macOS 27, which it calls Golden Gate, on September 14. Since then the same few problems have turned up again and again in Apple's support forums and in troubleshooting guides. Here they are, with what causes each one.

"My Mac won't offer me macOS 27"

If Software Update keeps offering you a macOS 26 update and never 27, your Mac probably can't run it. macOS 27 runs only on Macs with Apple's own chips (M1 or newer, plus the new MacBook Neo). No Intel Mac can install it.

To check which kind you have, open the Apple menu and choose About This Mac. If the line for the chip says Apple M1 or later, you can upgrade. If it names an Intel processor, macOS 26 is the last version your Mac gets.

That doesn't mean an Intel Mac has to go tomorrow. But Apple doesn't publish a date for when older versions of macOS stop getting security fixes, so this is a good moment to start planning what replaces it.

"My printer stopped working"

After the upgrade, macOS reports that the printer software isn't compatible, or print jobs just never arrive.

What's usually going on: many older printer drivers were written for Intel Macs. On an Apple silicon Mac they run through a translation layer called Rosetta. Several printer makers and IT support companies report that Rosetta isn't installed after upgrading to macOS 27, and their drivers fail without it.

Try these in order:

1. Re-add the printer using AirPrint. Open System Settings, then Printers & Scanners. Remove the printer, add it again, and when you choose it pick AirPrint instead of the manufacturer's driver if it's offered. AirPrint is built into macOS and needs no driver at all. Brother, for one, now recommends AirPrint for macOS 27.
2. If you need the full driver, check the manufacturer's site for a version that supports macOS 27.
3. As a stopgap, install Rosetta. Apple's own instructions are to open an Intel app and approve the prompt, or to open Terminal and run softwareupdate --install-rosetta. That can get an old driver working again, but see the next section for why it's only a stopgap.

"Some of my apps warn me they'll stop working"

They will, next year. Apple has said that macOS 27 is the last version where Rosetta works for apps in general. From macOS 28, apps built only for Intel Macs won't open. The only exception Apple has announced is some older games.

You don't have to guess which apps are affected. macOS 27 lists them for you:

1. Open System Settings, then General, then About.
2. Next to Intel-based Apps, click Details.

For each app on that list, look for an update or a replacement now while you have a year to do it. A program you use once a year, like tax software or the utility that came with a scanner, is easy to forget until the day you need it.

"My work email stopped syncing in Mail"

The change behind this one comes from Microsoft. If your employer's email runs on Microsoft 365 (also called Exchange Online), Microsoft began switching off an older connection method called Exchange Web Services on October 1, 2026. It's rolling out organisation by organisation, and it switches off for good on April 1, 2027.

The Mac versions of Mail and Calendar still use that method for Microsoft 365 work accounts. Apple says it's working with Microsoft to move Mail, Calendar, Contacts, Notes and Reminders to Microsoft's newer system "in a future update to macOS 27," but that update hasn't come out yet.

• iPhone and iPad aren't affected. They connect a different way.
• Companies that run their own Exchange server aren't affected. Microsoft's change applies only to its cloud service.
• What to do: tell your IT department. They can keep the old method running for now, but only until April 2027. Or use Microsoft's own Outlook app on the Mac, which isn't affected.

"Mission Control and Spaces are glitchy"

Some people report stuttering, long pauses, or black previews when switching between desktops or full-screen apps. Macworld says MacGeneration reproduced some of these problems. Apple hasn't said when it will fix them. macOS 27.2 has been in testing since mid-September and reached the release candidate stage on October 19, so a release may not be far off.

For now, keep your Mac up to date. If it bothers you, avoid full-screen mode and use ordinary windows until the fix arrives.

What I do about it

If you're on macOS 27 and something above doesn't fit what you're seeing, or the fixes didn't take, call me. I'll find out what broke and fix it. If your Mac is an Intel model that has reached the end of the line, I'll give you a straight answer about whether it's worth keeping.

Call (503) 567-5975 or email support@ironwood.help.

Sources

• Apple: macOS 27 Golden Gate is compatible with these computers, the complete list, all Apple silicon
• Macworld: macOS 27 Golden Gate: what's new, release date and compatibility, covering the September 14 release, the 27.0.1 update, and the Mission Control and Spaces reports
• 9to5Mac: First release candidate for macOS 27.2 (October 19, 2026)
• Apple: Using Intel-based apps on a Mac with Apple silicon, covering Rosetta through macOS 27, the macOS 28 cutoff, the Intel-based Apps list and installing Rosetta
• Apple Developer: Upcoming changes to Rosetta support (September 1, 2026)
• Brother: macOS 27 support status, which recommends AirPrint
• Apple Platform Deployment: Integrate Apple devices with Microsoft Exchange, which says Mac uses EWS and iPhone and iPad use ActiveSync, with Graph support due in a future macOS 27 update
• Microsoft 365 Message Center: MC1227454, EWS retirement update, with blocking from October 1, 2026, permanent removal after April 1, 2027, and Exchange Server on-premises unaffected
• MacRumors: Microsoft 365 work accounts may stop syncing in Apple Mail (October 1, 2026)