Once Big Sur is installed is there anyway to revert back to an earlier configuration

Miket9 Said:

"Once Big Sur is installed is there anyway to revert back to an earlier configuration: wife has a Mac mini 2014 with Big Sur installed runs very slow. Can I revert to back to earlier so version of high Sierra"

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Reinstall the macOS Anew:

The ultimate workaround would be through a new install.

Reinstalling the macOS Anew:

Try This:

1. First, Backup your Mac, then

2. Then, install your chosen, compatible macOS anew.

3. Finally, migrate it over from the Backup created in step 1

In Depth:

1. Back up your Mac:

Start by Creating a Time Machine Backupof my Mac. That way I could be assured that Incan recover my Mac, should I need the App back or if anything goes wrong due to the removal. So, Create a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the reinstall.

2. Use a USB Bootable Installer:

Create a USB Bootable Installer for the macOS. Delete the hard drive's partition. Then, install this macOS with. Go Here: How to Create a Bootable Installer for macOS - Apple Support.

3. Migrate and Reinstall Data and Apps:

Next migrate it over from the Time Machine Backup you created in step 1 to this new install.

See "Other macOS installation options" in

How to reinstall macOS - Apple Support

I had the same issue at first. My Mac Mini came with a "fusion" drive, which includes a 128GB SSD and a 1TB HDD "fused" into a single drive. This had its own problems some time ago, so I followed some online instructions and "split" them. At first I had installed Big Sur on the HDD because it was bigger and had more space. THAT is where the problem lies. The 5400RPM HDD is WAY too slow for Big Sur. Every time I moved my mouse, the little rainbow ball would spin and spin. I couldn't get anything done. Even launching Safari or Chrome slowed it down.

At first I thought it was the synchronization with iCloud, so I turned that off, but it didn't help. When I found some suggestions online to install Big Sur on an external SSD, I figured that could solve it. There was no data left on the 128GB internal SSD, so I just put Big Sur onto an external thumb drive and installed it on the open SSD.

There are absolutely NO problems anymore. I can use basic programs easily. I can also use Photoshop and InDesign without a problem. No more spinning wheels for me.

A few things I learned:

There are some caveats they they DO NOT tell you about downgrading. All of the instructions I read say you have to backup your data if you choose to downgrade. I downgraded to Catalina on the 128GB SSD first, but I couldn't access any of the files on the HDD. That is because Apple introduced a new file system with Big Sur: AFP. The default version of Catalina cannot access those files because Catalina runs on Apple Extended with Journaling. AFP can read AEJ, but AEJ cannot read AFP. (Maybe with some tools I haven't found yet.)

If you downgrade or choose the option I selected by installing the operating system on another drive, you may have to re-install some applications. While some will run off the HDD, they will run faster on the SSD with the OS.

Good luck. I hope this helps!

An easy solution is if you made a bootable clone of your previous OS/system using either CarbonCopyCloner or SupereDuper.

First, boot into your clone. Then you need to erase the entire disk using Disk Utility in recovery and reformat the drive Mac OS Extended. When that is finished, quit Disk Utility and clone back from the clone. You will have your old system back totally intact - nothing to transfer or port over.