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Updating from Catalina to Big Sur am getting Checking "(null") and Incompatible Disk messages

Would be very grateful for help. Update to Big Sur has stalled on the "(null)" message

MacBook Air 13″, macOS 11.2

Posted on Sep 18, 2021 8:32 PM

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Posted on Sep 21, 2021 2:51 AM

If possible while in Disk Utilities >> View >> View ALL attached Drives. Please provide a Screen Shot or Picture and post back. It seems you might be attempting to remove a Volume called Macintosh HD and anther called Macintosh HD - Data. If that is so, be very very careful. Both of this are Required for the OS to function.

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Question marked as Top-ranking reply

Sep 21, 2021 2:51 AM in response to airrlaing

If possible while in Disk Utilities >> View >> View ALL attached Drives. Please provide a Screen Shot or Picture and post back. It seems you might be attempting to remove a Volume called Macintosh HD and anther called Macintosh HD - Data. If that is so, be very very careful. Both of this are Required for the OS to function.

Sep 19, 2021 4:26 PM in response to PRP_53

Thank you for the helpful response. I am trying to rebuild my teenage grandson's machine - clogged with the residues of 100 video games. I am not an expert and the help has been very welcome. In the end I have succeeded by:


> Taking care to go back and erase absolutely everything in each of the volumes; the first attempt seemed to have left a few GB behind - maybe contributing to the Incompatible Disk message

> NOT using the Reinstall option in the Recovery App (which took me to Mojave) - and expecting to "climb back" through the updates.

> Instead, do a new Restart and use the Option-Command-R route (See Reinstall macOS webpage) to install the latest compatible OS - taking me direct to Big Sur. This seems to have dodged round the Checking "(null)" message.

> This worked - but I got messages suggesting that my WiFi link was not working; maybe I could have persisted, but in line with your message I used an ethernet connection (Happily I have a USB/ethernet adaptor)

> I am left with two "surplus" volumes which have "turned up" so I will need to tidy them up.


Thank you again

Sep 20, 2021 4:33 PM in response to PRP_53

Hi,


I can see the "surplus" internal Volumes in Disk Utility (Apps/Utilities) but I can't erase or delete them there. The additional Volumes seem to be a by-product of the OS Restore processes - where I tried several routes. Back at the start of my "clean-up" process I managed to erase the original Volumes (though in two steps), and also to delete one unwanted Volume, using the Disk Utility in the Recovery App.


So I will go back to the Recovery App to remove the unwanted Volumes. Hope this makes sense


A

Updating from Catalina to Big Sur am getting Checking "(null") and Incompatible Disk messages

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