Big Sur installation hung up system preventing restart

Installing Big Sur hung up with "less than a minute" left in installation time. The system will not restart normally and asks if I want to restart in "target disk mode". Is hooking up to another Mac with Thunderbolt cables the way to proceed?

Posted on Feb 12, 2021 3:01 PM

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2 replies

BDAqua

Level 10

250,181 points

Feb 12, 2021 3:27 PM in response to noel356

I'd hold the power button in until it shuts down, wait 5 minutes & try powering up.

noel356 Author

Level 1

8 points

Feb 12, 2021 4:42 PM in response to BDAqua

Thanks, but still prompts for re-start in "target mode".

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Big Sur installation hung up system preventing restart

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