This Disk is Locked (Mac OS Big Sur - Mac OS Catalina)

Hi guys, I tried the new Mac OS Big Sur Beta on my iMac 27” 2017, the problem is I accidentally wiped the entire Mac OS system in order to downgrade from Big Sur to Catalina. Now when I want to re-install Catalina it says that “This Disk is locked”, the continue button is grayed, I can’t click on it.

Any help?

iMac 27″ 5K, macOS 11.0

Posted on Sep 26, 2020 10:27 AM

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1 reply

Kappy

Level 10

362,007 points

Sep 26, 2020 11:22 AM in response to mervanpolat1

How are you doing this downgrade to Catalina? Please relate the steps you've taken. Did you erase the physical drive or just logical volume listed below the physical drive? Did you read the instructions provided for just such a download - Apple Beta Software Program?

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This Disk is Locked (Mac OS Big Sur - Mac OS Catalina)

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