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Trouble installing Big Sur

Trying to update to Big Sur.

I have downloaded successfully, I accepted the terms and conditions, then I get a message "select the disc where you want to install macOS". The only destination shown is my MHD, when I select this I get a message "This volume is not formatted as APFS" and I can get no further.

I admit to not being too tech savvy, maybe I shouldn't have started this.

Any help gratefully received.

All the Best

Nebb

MacBook Pro 13″, macOS 10.14

Posted on Nov 11, 2024 7:44 AM

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Question marked as Top-ranking reply

Posted on Nov 11, 2024 10:42 AM

Try to install macOS Catalina first: App Store - macOS Catalina.


You indicate using macOS Mojave. Please know that macOS Catalina and later versions (including macOS Big Sur) are no longer compatible with 32-bit applications.

20 replies

Nov 18, 2024 6:11 AM in response to nebb1

Hello nebb1,


In Disk Utility, click the View icon to show all the devices:



You should then see elements (called volumes or containers) under the name of your internal drive. I believe this is those elements that can be converted. I write “I believe” because I don’t have any Mac on which I can actually test an APFS conversion.


I’m going to ask Mac experts to join this thread and provide guidance.

Nov 12, 2024 4:16 AM in response to nebb1

Hello nebb1,


  1. In Finder, go to the Applications folder, delete the file “Install macOS Big Sur” and empty the Trash to recover storage space.
  2. This article will show you how to find the 32-bit applications on your Mac. For each of them, go to the developer website to see if they offer a 64-bit version. Often they won’t state the 64-bit compatibility but will mention the compatibility with macOS Catalina or later, which is really what you need. Once macOS Catalina is installed, go to the developer website to download the 64-bit version of their app. Then delete the 32-bit version.

Nov 21, 2024 8:01 AM in response to nebb1

Hello nebb1,


Great! Now:


  1. Start the Mac in recovery mode first: shut off the Mac, start the Mac pressing the command + R keys, keep pressing the keys until you see the recovery screen.
  2. Open the Disk Utility.
  3. Select "MHD" (just like in your screenshot.) If you don't see "MHD", click View > Show All Devices in the menu bar.
  4. Right-click "MHD" and choose "Convert to APFS".

Nov 12, 2024 12:59 AM in response to 6x6

Hello 6 x 6

Thanks for your reply. Before I download Catalina two questions please, Having downloaded BigSur I have memory used that I could do with getting back, how do I get rid of that download? I was aware that 32-bit applications would be incompatible, but the applications I am using are still in everyday use so I think I should be able to update to the 64-bit format, any advice about that transition? The reason I want to change my OS is because I have several apps that can no longer update whilst I keep using Mojave. Thanks again.

Nov 13, 2024 12:29 AM in response to nebb1

Hello 6 x 6

Right, did like you said and removed BigSur, bookmarked the article about 32-bit apps and downloaded Catalina. I'm hesitant now about proceeding to installation as I've got some other unavoidable commitments and will have to leave the next step until the weekend.

So if it's ok with you, I'd like to leave the topic open until then so I can let you know what happens.

Thanks for all your help thus far.

nebb

Nov 17, 2024 7:36 AM in response to nebb1

Hello 6 x 6

Hello I’m back, Panic over. Sorry about that.

I checked the situation with applications and I had only three 32-bit apps, one was third party and I binned it, the other two were quicklook and inkserver which I imagine will renew as 64-bit with the update.

When I tried to install Catalina, at the step “Select the disk where you want to install macOS”, I got a message “This volume is not formatted as APFS” the volume showing was my MHD.

I was not confident enough to go any further but when I looked in Disk Utility, in the LH column, underneath the heading Disk Images there was a disc icon with “Install ESD” written alongside, I have not seen that there before.

At this point, again your advice would be gratefully received.

nebb

Nov 18, 2024 5:39 AM in response to nebb1

Hello 6 X 6

Thanks for staying with me.

I’ve read the reply from @leroydouglas, complex! The easiest course for me seems:-


{2. Restart the Mac into Recovery Mode. To do that, select Restart from the Apple menu and hold down the Command and “R” keys (often abbreviated as CMD+R) until you see the Apple Logo or a spinning globe. You’ll be dropped into the macOS Utilities.


3. Launch Disk utility. Click-select your named boot volume. (Not the physical drive above it.) In this example, it’s called “John’s-MacBook.”


4. In the Disk Utility Edit menu, select “Convert to APFS.” (It will be dimmed if you didn’t properly select the boot volume.)


I’m preparing to follow the above instructions but being a bit hesitant I would like to check a couple of things please.


Just looking in Disk utility before going in to Recovery Mode, in the LH column I have a heading “Internal” below which is a disc icon with MHD alongside, below that another heading “Disk Images” below which is a disc icon with InstallESD alongside. When in recovery mode I am going to click on MHD, right?


If I click on that now, just to see and before being in recovery mode, convert to APFS in Edit is greyed out but presumably it will not be greyed out when in recovery mode, I hope.


nebb

Trouble installing Big Sur

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