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Unable to install macOS Big Sur on my iMac

unable to install macOS Big Sur on my iMac

iMac 21.5″, macOS 10.15

Posted on Mar 1, 2023 6:37 PM

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Question marked as Top-ranking reply

Posted on Mar 1, 2023 6:40 PM

Hi there!


In order to start diagnosing your Mac, we first need to know some information about it. 


To start, using this Apple Support article as a guide, Get system information about your Mac, let us know what year your Mac is, the model, and what version of macOS you are currently using.


Also, please let us know what error you see when attempting to install macOS Big Sur 11.


Jack

13 replies
Question marked as Top-ranking reply

Mar 1, 2023 6:40 PM in response to 24boca

Hi there!


In order to start diagnosing your Mac, we first need to know some information about it. 


To start, using this Apple Support article as a guide, Get system information about your Mac, let us know what year your Mac is, the model, and what version of macOS you are currently using.


Also, please let us know what error you see when attempting to install macOS Big Sur 11.


Jack

Mar 2, 2023 7:35 AM in response to 24boca

The iMac is a mid 2014 21.5” which Apple indicates is capable to run Big Sur. It has a 1Tb hard drive. It currently is running Catalina 10.15.7 for over a year. It is Ethernet connected and typically downloads 350mbs. Able to download 12.41gb of 12.41gb. At that point it appears the system may be trying to install but gives msg An error occurred while installing the selected update. I have been at that point several times.

Mar 7, 2023 4:20 PM in response to 24boca

Thanks for everyone that offered suggests to solve my problem downloading and installing Mia big sur. Attempted most but none weee successful. Turned to Apple support and worked with 4 tech. Had no positive results with 3. Last tech was very knowledgable and took my system directly to Apple severs. Start in Safe mode then hold down Control,Command, the R key. Seemed to eliminate the glitch between download and install. Ended up at my local store and they did same step and was successful

Unable to install macOS Big Sur on my iMac

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