How do I fix an iMac freezing on startup?

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Level 1

47 points

How do I fix an iMac freezing on startup?

iMac freezing on startup.

When I came in this morning the iMac was off, even though it had been left on. When I pressed the power it showed the apple logo then went to the startup screen (in my case the Sequoia background) but the loading bar reaches around half way and freezes. I tried re-starting several times but same thing.

So I tried re-starting in Recovery mode and hit CMD-R after pressing start (it's intel) which brought up the black screen with apple logo and again that froze, staying on the screen with the apple logo for around 15 minutes while I pottered around doing other things.

Finally after checking the forum here I tried resetting NVRAM by holding CMD-OPT-P-R. This resulted in a much louder start up sound than normal (normally this imac is really quiet on startuo compared to previous iMacs and Macbooks I've had so the sound was actually same loudness as normal macs). But again this froze on the startup screen and the loading bar sitting at halfway, as pictured below. It's still like that now despite me now typing for 5 minutes.

What can I do now? I really need to get this working asap.

I'm sorry I can't provide more details about the mac itself (I think it's maybe 2017...if it were switched on I'd provide specs etc which I can't remember offhand just now)

Thanks in advance.

[Re-Titled by Moderator]

Original Title: iMac freezes on startup

iMac 27″

Posted on Feb 15, 2026 2:46 AM

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Answer 1

Top-ranking reply

den.thed

Level 10

94,536 points

Feb 15, 2026 9:34 AM in response to gkmach1ne

This is starting to sound like a failing drive.

Disconnect your backup drive and other devices.

Try reinstalling the macOS over the top of the current version.

How to reinstall macOS - Apple Support

If that doesn't work, Erase and reinstall in macOS Recovery Mode.

Then if the erase and reinstall takes, migrate from your backup during the setup.

Use Disk Utility to erase an Intel-based Mac - Apple Support

Then if that doesn't work...?

Consider replacing with a new, instead of spending money on that 8 or 9 year old Mac.

Then migrate from your backup when setting up the new Mac.

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Answer 2

den.thed

Level 10

94,536 points

Feb 15, 2026 8:02 AM in response to gkmach1ne

Hold the power button for 10 seconds or until the iMac completely shuts off.

Unplug the power cord for 60 seconds, then plug in and press the power button.

If that doesn't startup, see > If your Mac doesn't start up all the way - Apple Support

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Answer 3

gkmach1ne Author

Level 1

47 points

Feb 15, 2026 11:38 AM in response to den.thed

H again

Thanks for response again...this I dare say, as much as I hate to admit that it might have a failing disk, is probably what the issue is.

I've managed to get it into Recovery mode again and am in the process of reinstalling the OS.

Incidentally, I did manage to start it in Safe Mode an hour ago and managed to do a back up at that point. While in SM I was also able to do a first aid on the main container and was told there was something corrupt that was unfixable. I pasted the results/information into a doc so I could look at it later.

And I just found the receipt for the iMac, it's a 2019 model and I only bought it in November 2024, refurbished. It's got a 2TB SSD and a 3.6GHz processor and 32GB memory.

I'll let you know how it goes...thanks again.

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Answer 4

gkmach1ne Author

Level 1

47 points

Feb 15, 2026 8:10 AM in response to den.thed

Hi den.thed

Thanks for your input.

Yes, I did try this too (unplugging) but to no avail.

However, on my 6th or 7th attempt at opening in Recovery Mode (which I thought was unsucessful as it had been stuck for 30 mins) I went out for a walk to clear my head and when I returned an hour later I found it to be in Recovery mode. I tried first aid on all disks and was told first aid was completed so attempted to restart. Unfortunately however I'm back on a frozen startup.

Regarding the link you sent, none of those apply (or do they?) to what I'm experiencing. My screen is frozen in this view:

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