There are various reasons why you might want to get back to an older version of Mac OS. Perhaps the software that you are currently working on is not compatible with Mac OS or maybe you are just not comfortable with the new version. Although Mac needs updated versions to work on, there are a few ways you can revert back to an older version.
Prerequisites you need to know before downgrading Mac OS Sierra
Backup! This is very essential if you are keen on keeping your files and folders. If you have a Time Machine with a drive plugged in, regular backups would’ve been made, so you are safe. But in case, there is no backup, then backing up now would even backup your present Mac version.
Downgrade to the OS that your Mac was shipped with
It has always been an incredible feature in Mac OS recovery since Mac OS Sierra 10.12.4 to get back to the version of Mac, you bought the system with. Follow the simple steps to accomplish this:
- Shut down your Mac. As you restart, press Shift-option/Alt-Command-R altogether.
- Once you see the Mac OS utility screen, choose reinstall Mac OS.
- Click on Continue button and follow the onscreen instructions.
- Select Startup disk and click on Install.
- Once the installation is complete, Mac will restart and the OS would have been downgraded to the version, the Mac was shipped with.
Downgrade Mac OS using Time Machine
It is always recommended to store a backup of your data for obvious reasons. Time Machine is a backup software application that is a part of Mac OS. It creates the incremental backup of files that can be restored at a later date. It allows you to restore the whole system or specific files back into the system in case of data loss blunders. Check here to know how to revert from Mac OS Sierra to OS X EI using Time Machine. Follow the steps below to downgrade Mac OS using the Time Machine:
- Insert the Time Machine disk into your Mac and click on the apple logo. Select Restart.
- Hold down Command + R until the apple logo
- A list of options appears on the screen. Choose Restore From Time Machine Backup and click Continue.
- Again select Restore From Time Machine Backup when prompted and click on
- Select any Restore Source. your back up drive that holds all your backed up data.
- Next screen will show you all your backups over time. Pick the recent one that you made before downgrading your OS.
- The previous version is installed and you can retrieve all your files from the backup that you selected.
Downgrade Mac OS without using Time Machine
In case you don’t have a backup, you can still downgrade your Mac OS using a Bootable Installer of Mac OS. You can follow the steps below to create a Bootable Installer of Mac OS.
- Plug in an external drive of about 8GB into your system.
- Press Cmd + Spacebar and type Disk Utility.
- Click on the View Drop Down below the close-minimize
- Choose Show All Devices from the options to see the external root drive.
- Select the Root Drive in the sidebar and click on Erase.
- Pick Mac OS Extended (Journaled) as the format.
- Choose GUID Partition as the scheme and give your drive a name to recognize it.
- Click on Erase
- It will take a few minutes to create the partition and set up the drive. Once done, click on Done.
- Press Cmd + Space Bar and type Terminal to open Terminal.
- Copy the following lines into the terminal and click Enter:
Sudo /Applications/Install\ macOS\ High\Sierra.app/Contents/Resources/createinstallmedia –volume /Volumes/MyVolume –applicationpath /Applications/Install\ macOS\ High\ Sierra.app
- Terminal will ask for password. Type and press Enter.
- The terminal will start erasing your disk to copy the installer file to your drive.
- Now you have the installer on the external drive you can use that to install multiple copies of macOS. Plug the external drive into your Mac that you want to install the macOS on.
- Start the Mac holding the Option + Alt key while it is booting up.
- Your Mac will display the Startup Manager, click on your external drive and select Install macOS.
After creating a Bootable Installer of Mac OS, follow these steps to downgrade Mac OS:
- Shut down your Mac.
- Plugin the external drive that contains your bootable installer.
- Start up the Mac holding down the Option/Alt + R while it is booting up.
- Your Mac will start up in the Recovery Mode and a Mac OS utility screen will appear, select Disk Utility and click on Continue.
- Select your Startup Disk and click on Erase.
- Choose one of the Mac OS Extended (Journaled) formats.
- Restart your Mac and select the boot drive you created.
- You should be able to install the older version of Mac OS.