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Can I boot and use Catalina from external disk after I upgrade my computer to Big Sur?

Can I boot and use Catalina version from an external disk after I upgrade my computer to Big Sur?


Is there any update in the version of the system parts with Big sur update?


Thanks

MacBook Pro 13″, macOS 10.15

Posted on Apr 30, 2021 3:57 AM

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Question marked as Top-ranking reply

Posted on Apr 30, 2021 4:05 AM

Yes, you can boot in Catalina from an external disk after installing Big Sur.


Depending on your mac model, you may have to allow booting from an external drive in Startup Security - that is true not just for Catalina, and it applies to macs with T2 chip (which is most of the intel macs from last two or three years, I believe).


To change the settings in Startup Security, follow the instructions here:


https://support.apple.com/en-us/HT208198



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Question marked as Top-ranking reply

Apr 30, 2021 4:05 AM in response to kadir266

Yes, you can boot in Catalina from an external disk after installing Big Sur.


Depending on your mac model, you may have to allow booting from an external drive in Startup Security - that is true not just for Catalina, and it applies to macs with T2 chip (which is most of the intel macs from last two or three years, I believe).


To change the settings in Startup Security, follow the instructions here:


https://support.apple.com/en-us/HT208198



Can I boot and use Catalina from external disk after I upgrade my computer to Big Sur?

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