Apple fixes a bug causing some Macs to fail to boot after installing macOS Monterey

Apple has acknowledged that it has managed to squish a bug in the Mac operating system that caused some Mac computers from failing to boot after installing macOS Monterey.

A still from Apple's presentation with Craig Federighi standing in front of a slide with the text "macOS Monterey"


  • Some users complained about bricked Macs after updating to Monterey
  • The culprit: a bug in the firmware on the Apple T2 security chip
  • macOS Monterey includes a fix for this issue

Apple fixes macOS Monterey boot issues

A bunch of posts on Apple’s forums suggest that macOS Monterey causes some Macs to refuse to boot. In some instances, users report Macs unable to turn on at all. This isn’t the first time we heard about boot problems after installing a macOS update, so this one shouldn’t come as a surprise. Read: Useful keyboard shortcuts for starting up your Mac

Thankfully, Apple seems to have managed to fix this problem in a matter of days. The company issues a statement to Rene Ritchie confirming that there’s an issue with the firmware that has now been resolved. Also, a fix is included in the existing updates.

Here’s Apple’s statement to Richie in full:

We have identified and fixed an issue with the firmware on the Apple T2 security chip that prevented a very small number of users from booting up their Mac after updating macOS. The updated firmware is now included with the existing macOS updates.

But how do you install the update if the bug has already rendered your Mac useless, refusing to boot or even turn on? Well, any users impacted by this issue “can contact Apple Support for assistance,” as the company wrote in its response.

A support document on the Apple website says that a Mac may become unresponsive in the unfortunate event of a power failure occurring during a macOS update or upgrade. Should that happen to you, your Mac “may become unresponsive and so the firmware must be revived or restored,” the company notes.

If the very thought of taking your Mac to a nearby Apple store is driving you nuts, you may try to revive the T2 chip yourself by following the instructions in the aforementioned support document. Basically, you’ll need a second computer with the same or higher operating system version to unbrick your Mac.