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Why can't I download Big Sur? My currnet operating system is El Capitan, version 10.11.6 and I seem to have all the necessary requirements.

Why can't I download Big Sur? My currnet operating system is El Capitan, version 10.11.6 and I seem to have all the necessary requirements.

iMac 21.5″, OS X 10.11

Posted on Mar 6, 2021 11:52 AM

Reply
Question marked as Top-ranking reply

Posted on Mar 6, 2021 10:04 PM

What mac model and year is your mac, click on the top left of your screen and click on About This Mac.


macOS Big Sur is compatible with these computers:


MacBook introduced in 2015 or later

MacBook Air introduced in 2013 or later

MacBook Pro introduced in late 2013 or later

Mac mini introduced in 2014 or later

iMac introduced in 2014 or later

iMac Pro

Mac Pro introduced in 2013 or later

View the complete list of compatible computers.

If upgrading from macOS Sierra or later, macOS Big Sur requires 35.5GB of available storage to upgrade. 

If upgrading from an earlier release like Mac OS X El Capitan, macOS Big Sur requires up to 44.5GB of available storage. To upgrade from OS X Mountain Lion, first upgrade to OS X El Capitan, then upgrade to macOS Big Sur.


As you can see from the above if you are upgrading to Big Sur directly from El Capitan you need at least 45.5GBS of free space.

Although Apple say you can upgrade directly from El Capitan to Big Sur I would not recommend it. Part of the installation is converting your file system from HFS+ to the newer APFS. There have been reports that upgrading from an early OS like El Capitan to Big Sur can result in the installation hanging and the mac becoming unusable.


I would recommend doing an intermediary upgrade to macOS High Sierra, this should provide the necessary firmware

to convert the file system to APFS.


For macOS High Sierra,


Open Safari and click on this link, 

How to get old versions of macOS – Apple Support

Go to the Download OS section and click on macOS.


Before upgrading make a full back up of your Mac.


Check that third party apps you use have updates available for the new OS.

https://roaringapps.com

Check that your printers/ scanners etc have updated drivers and software available for the new OS.


Connect your mac to your router via cable rather than rely on WiFi.

Do not use your mac while it is downloading

and do not use any other devices that share the same internet connection.


If the App Store says ‘Open’ then it is detecting a previous download of the install app

go to the Applications folder locate Install macOS ******.app.

Move it to the Trash, empty the Trash.

Restart, click on the link again, the App Store should say ‘Get' or 'Download'.


If you want to or are able to install Big Sur, open Safari and click on the link below.

How to upgrade to macOS Big Sur - Apple Support


If you are considering upgrading to Big Sur be warned it does not support 32bit apps.

Your Mac is probably running 32bit apps and these will need to be updated to 64bit apps,

some updates may be free, some may be paid. Use this app to discover which apps you have

are 32bit, https://www.stclairsoft.com/Go64/ then contact the developers of the software to see

if they are offering 64bit updates.


Big Sur is a very different OS to El Capitan so make sure you are fully up to speed as to how this will

affect you and the way you use your mac.


1 reply
Question marked as Top-ranking reply

Mar 6, 2021 10:04 PM in response to amimegusta

What mac model and year is your mac, click on the top left of your screen and click on About This Mac.


macOS Big Sur is compatible with these computers:


MacBook introduced in 2015 or later

MacBook Air introduced in 2013 or later

MacBook Pro introduced in late 2013 or later

Mac mini introduced in 2014 or later

iMac introduced in 2014 or later

iMac Pro

Mac Pro introduced in 2013 or later

View the complete list of compatible computers.

If upgrading from macOS Sierra or later, macOS Big Sur requires 35.5GB of available storage to upgrade. 

If upgrading from an earlier release like Mac OS X El Capitan, macOS Big Sur requires up to 44.5GB of available storage. To upgrade from OS X Mountain Lion, first upgrade to OS X El Capitan, then upgrade to macOS Big Sur.


As you can see from the above if you are upgrading to Big Sur directly from El Capitan you need at least 45.5GBS of free space.

Although Apple say you can upgrade directly from El Capitan to Big Sur I would not recommend it. Part of the installation is converting your file system from HFS+ to the newer APFS. There have been reports that upgrading from an early OS like El Capitan to Big Sur can result in the installation hanging and the mac becoming unusable.


I would recommend doing an intermediary upgrade to macOS High Sierra, this should provide the necessary firmware

to convert the file system to APFS.


For macOS High Sierra,


Open Safari and click on this link, 

How to get old versions of macOS – Apple Support

Go to the Download OS section and click on macOS.


Before upgrading make a full back up of your Mac.


Check that third party apps you use have updates available for the new OS.

https://roaringapps.com

Check that your printers/ scanners etc have updated drivers and software available for the new OS.


Connect your mac to your router via cable rather than rely on WiFi.

Do not use your mac while it is downloading

and do not use any other devices that share the same internet connection.


If the App Store says ‘Open’ then it is detecting a previous download of the install app

go to the Applications folder locate Install macOS ******.app.

Move it to the Trash, empty the Trash.

Restart, click on the link again, the App Store should say ‘Get' or 'Download'.


If you want to or are able to install Big Sur, open Safari and click on the link below.

How to upgrade to macOS Big Sur - Apple Support


If you are considering upgrading to Big Sur be warned it does not support 32bit apps.

Your Mac is probably running 32bit apps and these will need to be updated to 64bit apps,

some updates may be free, some may be paid. Use this app to discover which apps you have

are 32bit, https://www.stclairsoft.com/Go64/ then contact the developers of the software to see

if they are offering 64bit updates.


Big Sur is a very different OS to El Capitan so make sure you are fully up to speed as to how this will

affect you and the way you use your mac.


Why can't I download Big Sur? My currnet operating system is El Capitan, version 10.11.6 and I seem to have all the necessary requirements.

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