IMac reboots in Big Sur instead of newly installed Ventura

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Level 1

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IMac reboots in Big Sur instead of newly installed Ventura

I have a 2019 iMac running Big Sur. I have tried to download and install Monterey and Ventura (separate tries) and both upgrades fail. the new OS will download but the install process seems to get cut short and the computer restarts back in Big Sur. I have already confirmed that there is plenty of space on my hard drive for the install (almost 1 gig free). Any ideas on how I can get the computer to update its OS to Monterey or later ( I want to use universal control because I have two Macs sitting side by side). Help please.

iMac, macOS 10.12

Posted on Dec 22, 2022 8:32 AM

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Answer 1

Top-ranking reply

Old Toad

Level 10

210,585 points

Dec 22, 2022 2:50 PM in response to austinmacs

Then you should make an appointment at the nearest Apple Genius Bar or Apple Authorized Service Provider and have that checked. It should be able to install the firmware update if it's an Apple drive.

You might try creating and logging into a new, basic, admin user account, Set up users, guests, and groups on Mac, and stry to install from there.

Note: do not launch any 3rd party apps in the account so as to not install any of the supporting files that most create.

If that fails then make the appointment.

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Answer 2

dialabrain

Level 10

125,207 points

Dec 22, 2022 8:39 AM in response to austinmacs

If you meant almost 1 TB, try upgrading in Safe Mode.

How to use safe mode on your Mac - Apple Support

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Answer 3

Old Toad

Level 10

210,585 points

Dec 22, 2022 11:08 AM in response to austinmacs

Note: if you have a wireless keyboard with rechargeable batteries connect it with its charging cable before booting into Safe Mode. This makes it act as a wired keyboard as will assure a successful boot into Safe Mode.

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Answer 4

austinmacs Author

Level 1

4 points

Dec 22, 2022 8:45 AM in response to dialabrain

It will reboot in recovery mode but when I try to reboot in safe mode it just boots normally. I have already rebooted in recovery mode and done a new install of Big Sur (hoping it would update something so then I could try to update to Ventura but the reinstall of Big Sur didn't help).

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Answer 5

austinmacs Author

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Dec 22, 2022 9:30 AM in response to dialabrain

I was able to reboot in safe mode and then tried to install Ventura. Same problem. I then restarted in recovery mode but it only gives me the option to reinstall Big Sur, which I have already done, so that didn't work either.

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Answer 6

dialabrain

Level 10

125,207 points

Dec 22, 2022 8:36 AM in response to austinmacs

1 GB is no where close to enough space to upgrade. It's also not enough space to run a Mac.

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Answer 7

austinmacs Author

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Dec 22, 2022 8:39 AM in response to dialabrain

Im sorry. I meant it has 1 TB free.

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Answer 8

dialabrain

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125,207 points

Dec 22, 2022 8:41 AM in response to austinmacs

austinmacs wrote:

Im sorry. I meant it has 1 TB free.

I figured. :) See my previous post.

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Answer 9

dialabrain

Level 10

125,207 points

Dec 22, 2022 8:49 AM in response to austinmacs

Try booting into Recovery Mode using option+command+R. It should offer to install the latest version of macOS you can run.

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Answer 10

dialabrain

Level 10

125,207 points

Dec 22, 2022 9:36 AM in response to austinmacs

Did you start up in Recovery mode using the key combination I posted and not just command+R?

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Answer 11

austinmacs Author

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4 points

Dec 22, 2022 12:08 PM in response to dialabrain

Yes. I used option, command +R and updated from the internet in recovery mode. It downloaded Ventura but the install failed with "required firmware update could not be installed."

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