MacOS won't boot

Question

Level 1

8 points

MacOS won't boot

This morning, I noticed my MacBook Pro wasn't running - it keeps getting part way through bootup (nearly to the end) before the fan kicks in on high and the machine shuts down.

I've managed to get to the recovery console and check the disk, which seems fine; after that I got as far as "spinning pinwheel" before it rebooted, now it's only getting to around 80-90% before rebooting.

With the fan kicking in and the fact that the machine is getting very warm, I was wondering if it was a thermal protection thing, but I've taken it to the coldest room in the house and am now cooling down my living room to no benefit.

I can't remember my time machine backup password and I'm not sure how recently it backed up, anyway.

Is there anything else I could do? I considered reinstalling the OS, but would that lose all of my own data? I don't want to wipe the HDD as it has some important stuff on it.

MacBook Pro 16″, macOS 10.15

Posted on May 10, 2021 1:10 AM

Reply

Answer 1

Best reply

leroydouglas

Community+ 2024

Level 10

184,080 points

May 10, 2021 7:23 AM in response to AdamEcc

AdamEcc wrote:

This morning, I noticed my MacBook Pro wasn't running - it keeps getting part way through bootup (nearly to the end) before the fan kicks in on high and the machine shuts down.

I've managed to get to the recovery console and check the disk, which seems fine; after that I got as far as "spinning pinwheel" before it rebooted, now it's only getting to around 80-90% before rebooting.

With the fan kicking in and the fact that the machine is getting very warm, I was wondering if it was a thermal protection thing, but I've taken it to the coldest room in the house and am now cooling down my living room to no benefit.

I can't remember my time machine backup password and I'm not sure how recently it backed up, anyway.

Is there anything else I could do? I considered reinstalling the OS, but would that lose all of my own data? I don't want to wipe the HDD as it has some important stuff on it.

If your Mac doesn't start up all the way

https://support.apple.com/en-us/HT204156 

If your Mac starts up to an Apple logo or progress bar

https://support.apple.com/en-us/HT207019

Reply

Answer 2

dominic23

Level 10

83,916 points

May 10, 2021 6:24 AM in response to AdamEcc

Backup your Mac as soon as possible if you can

Reset SMC: How to reset the SMC of your Mac - Apple Support Choose the appropriate method.

Quote:

Resetting the system management controller (SMC) can resolve certain issues related to power, battery, fans, and other features.

Startup in Safe mode. https://support.apple.com/en-gb/HT201262

To leave Safe Mode, click  in the menu bar and choose “Restart”

Quote:

Safe mode prevents your Mac from loading certain software when it starts up, including login items, system extensions not required by macOS, and fonts not installed by macOS. It also does a basic check of your startup disk, similar to using First Aid in Disk Utility. And it deletes some system caches, including font caches and the kernel cache, which will be created again automatically as needed.

About reinstalling macOS

https://support.apple.com/en-us/HT204904

Contact Apple Support.

Click inside the box to choose an option.

https://getsupport.apple.com/?caller=kbase&PGF=PGF63005&category_id=SC0245&symptom_id=23362

Reply

Answer 3

AdamEcc Author

Level 1

8 points

May 10, 2021 6:35 AM in response to dominic23

Thank you, I've now tried all those but to no effect :( The SMC reset doesn't appear to achieve anything (not that there's anything to indicate one way or the other), and attempting to go into safe mode results in a brief flash of corrupted graphics before the same fan burst and shut down.

The only responsive state I can get the machine to is the recovery console. I'm looking at the reinstall OS option, however I can't find any solid information as to whether my own data would be kept or if it's a complete system wipe that's carried out. Are you able to shed any light on that?

Reply

Answer 4

AdamEcc Author

Level 1

8 points

May 11, 2021 3:47 AM in response to leroydouglas

I'm tearing my hair out now... I've tried everything suggested here with no useful outcome

1) Resetting SMC didn't do anything noticeable

2) It won't boot up in safe mode, getting only slightly further than normal before the fan whirs up and it shuts down

3) I can get to recovery console, however attempting "reinstall macOS" fails 15 seconds before completion

4) I've tried "reinstall macOS" to a USB stick, too, and that also fails right before the end

5) I used my old MBP (earlier model) to create a bootable drive, which got to completion, however on the new machine it says it needs an update to be bootable... and that fails...

Given that "reinstall macOS" fails both to the HDD and to the USB, I'm wondering if the recovery image itself is damaged - any ideas on that?

Has anyone got a way of creating a bootable USB on a Windows machine? I've tried following a couple of guides but they seem to be out of date on certain aspects :(

Reply

MacOS won't boot

Similar questions