Big Sur on unsupported Mac. Installing Big Sur on an unsupported Mac can’t be done the regular way through System Preferences Software update.However, if the machine’s not too old, there’s still a way to install Big Sur on an unsupported Mac using a specially developed patcher tool. How To Upgrade an Older Mac To macOS Big Sur. Anyone with an incompatible Mac will have noticed that Software Update doesn’t give you the option to install Big Sur. To upgrade you’ll need a patcher to trick Software Update into thinking your computer is compatible. But before you get started, there are a few things you need to do. Restart your Mac and press 'alt' key until see the 'apple' logo, then select your USB ('Install macOS Big Sur') after go to 'Recovery' go to 'Terminal' from 'Utility menu' then: run command 'csrutil disable'. run command 'csrutil authenticated-root disable' select 'Install macOS' for 'Install macOS Big Sur' and select 'Your SSD' After.
macOS Big Sur elevates the most advanced desktop operating system in the world to a new level of power and beauty. Experience Mac to the fullest with a refined new design. Enjoy the biggest Safari update ever. Discover new features for Maps and Messages. And get even more transparency around your privacy.
Check compatibility
macOS Big Sur is compatible with the following computers. If your Mac isn't compatible, you might be able to install an old version of macOS instead.
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, your Mac needs 35.5GB of available storage to upgrade. If upgrading from an earlier release, your Mac needs 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.
Imac 2013 Big Sur
Download macOS Big Sur
If you're using macOS Mojave or later, get macOS Big Sur via Software Update: Choose Apple menu > System Preferences, then click Software Update.
Or use this link to open the macOS Big Sur page on the App Store: Get macOS Big Sur. Then click the Get button or iCloud download icon.
Install macOS Big Sur
After downloading, the installer opens automatically. Click Continue and follow the onscreen instructions.
Please allow installation to complete without putting your Mac to sleep or closing its lid. During installation, it might restart and show a progress bar or blank screen several times. You might find it easiest to begin installation in the evening so that it can complete overnight, if needed.
Stay up to date
After installing macOS Big Sur, you will be notified when updates to macOS Big Sur are available. To check for updates, choose Apple menu > System Preferences, then click Software Update.
Install Big Sur Macbook Pro Mid 2012
Install Big Sur On Older Mac
You start with creating a bootable USB with info from this post. Just pick Big Sur instead of the mentioned High Sierra.
Building/installing the patcher
After that follow these instructions,on how to install and use the OpenCore Legacy patcher.
Remarks
- Erase/format the MAC HD/SSD before installation !! I really think that this does it more simple for the installer !!
- With an old non SSD HD use 'Mac OS Extended(journaled)'
- With en SSD use 'APFS'
- The Mac rebooted several times during install.
- Don't remove the USB until at the very end.
- If you, like me, have a Mac which need the legacy video acceleration support please note that the Mac have a painfully slow display update before you have applied the 'Post-Install volume Patch'.
- Updating the Mac from Big Sur 11.4 to 11.5, made the messages.app stop working fixed in release 0.2.4
- Please note that 'Nightly Builds' are available but are for testing purposes only !!!
- In TUI '5. Miscellaneous Settings => 1. Set Showpicker Mode:' was set to 'False'