MacBook reboots like a new device after shutdown, Apple Account locked, and settings reset

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Level 1

4 points

MacBook reboots like a new device after shutdown, Apple Account locked, and settings reset

Hi everyone,

I recently faced a strange issue with my MacBook Air (M3, macOS 26.0.1).

After finishing my work, I shut down my Mac properly. While cleaning the screen, an unknown key was accidentally pressed, and suddenly my Mac turned on by itself.

When it started, it showed the “Hello” setup screen — just like a brand-new Mac. I was really shocked because it looked like everything was erased.

However, after checking, I found that:

All my data was still there, but
My Apple ID was locked,
All my system settings and customizations were gone,
The Dock icons were misarranged,
My desktop icons got randomly rearranged,
It felt like macOS reloaded my account as if it were a fresh setup.

Can anyone explain why this happened, and how to prevent it in the future?

Why did macOS suddenly show the Setup Assistant even though my data remained intact?

Thanks in advance for any help or insights

[Re-Titled by Moderator]

Original Title: MacBook suddenly booted up like a new device after shutdown — Apple ID locked, settings & Dock reset, and desktop icons rearranged

MacBook Air 13″, macOS 26.0

Posted on Oct 6, 2025 9:29 AM

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Answer 1

John Galt

Level 10

156,818 points

Oct 6, 2025 1:55 PM in response to sanju_000

I have no idea, but take it as an opportunity to create a backup: Back up your files with Time Machine on Mac - Apple Support.

What happened was inexplicable. You could ask Apple but I doubt they could provide any insight either.

For what it's worth you did not invoke any of that with an inadvertent key press, so you should not be concerned about pressing keys or anything else.

Just be sure to clean the screen (or the Mac in general) by following Apple's instructions, here: How to clean your Apple products - Apple Support. Lots of people come here asking what to do after they damaged the Mac, it won't boot, they didn't back it up... etc. By then it's too late.

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Answer 2

Oct 6, 2025 8:16 PM in response to sanju_000

No idea what happened with it appearing to go through Setup Assistant again. I didn't think it was possible except by erasing the system. I wonder if the macOS 26.0.1 update patch got installed when the system powered on again. I have seen the "Hello" screen after a minor OS update patch.

Just an FYI, pressing any key, or even the Trackpad itself can power on or wake the USB-C Macs. Also, connecting or disconnecting external devices can do so as well. Even opening the display clamshell lid can power on the USB-C Macs.

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