Need to install an older version of macOS on your Mac to revert to a specific version? In this article, we will explain How to install older versions of macOS or Mac OS X.
If you’ve come this far, chances are it’s because you want to install an older version of macOS or Mac OS X on your Mac. And that can be motivated by several reasons.
Maybe you are used to using software, and now you have discovered that it does not work exceptionally well with the latest version of macOS, so it would be perfect for returning to a previous version.
It may also be the case that you work as a developer and need access to multiple versions of macOS to make sure your software works well on all of them.
Or, you may not like the version of macOS you just installed and want to backtrack.
Whatever the reason you want to install an older version of macOS, the truth is that it is possible to do so, and in this article, we will explain the steps you should follow.
In case you want to move to the previous version of macOS that you currently have installed, you will be interested in reading our tutorial:
How to install an old version of macOS on your Mac
Now, it’s time to see the steps to follow to install an older version of macOS on your Mac: from checking if your Mac is compatible to downloading previous macOS versions, through the process to install them.
Step 1: Check if your Mac is compatible with that version of macOS
First, you’ll need to check that your Mac can effectively run the version of macOS or Mac OS X you want to install.
As a guide, your Mac will be compatible with the version of macOS or Mac OS X it came with when it went on sale and any version that has arrived after its purchase (until Apple has decided not to support it anymore).
That means there’s bad news: It’s doubtful that your Mac will be able to run a version of macOS or Mac OS X earlier than the one it had installed when you bought it.
You may not be able to install an older version of Mac OS X on a new Mac because the hardware drivers for the new Max didn’t exist when it was created in the old software.
What’s more, Macs can’t run a version of OS X earlier than the one they had installed when purchased, even if this version is installed on a virtual machine. The only solution is to get hold of an older Mac that is compatible.
Now, that does not mean that there are no exceptions. For example, suppose you bought a Mac in 2017 with specifications equal to its predecessor (or the model was introduced a few years earlier). In that case, you might be able to run an earlier version of macOS.
- Head to Apple’s support page for the macOS Mojave compatibility details
- If your machine can’t run Mojave, check compatibility for High Sierra
- If it’s too old to run High Sierra, try Sierra
- If no luck there, give El Capitan a try for Macs a decade old or more
Step 2: Download the version of macOS or Mac OS X you need
Next, you’ll need to download the installer for the version of Mac OS X or macOS you want to install.
The steps to follow may depend on the version in question, so we recommend you take a look at our article How to get older versions of macOS.
Step 3: Or search for an old backup in Time Machine
If you have a Backup to Time Machine before you update your Mac with the latest version of macOS, you’ll need to follow the steps below to do so.
Of course, remember that you will lose all that data created after the update, so it may be a good idea to save them so you can access them later. Here is a guide: How to Backup a Mac in Simple Steps
Step 4: Install the old version of macOS on your Mac
Once the installer is downloaded, you may think it’s as easy as clicking on it to get your Mac updated (or reverted to a previous version). By bad luck, it’s not that easy.
If you have a newer version of macOS installed on your Mac, you won’t be able to install an older version on top of it. You will need to completely reset your Mac before installing the old version of macOS or Mac OS X.
Don’t feel like doing it? You have several options. You could install the version you need on an external drive or also run two or more versions of macOS at once.
There are several methods to install an old version of the Mac operating system on your Mac. The best option for you will depend on several factors, such as whether you want to run more than one macOS simultaneously.
How to move to an older version of macOS with Time Machine
If you have a backup on Time Machine earlier than the macOS version currently installed, then this could be a relatively straightforward process for you.
Here are the steps to follow to recover a previous version of macOS from a backup in Time Machine:
1. Launch your Mac and immediately hold down the ‘Command + R’ keys.
2. Keep pressing the keys until you see the Apple logo or beach ball spinning.
3. When you see the ‘Utilities‘ window, choose ‘Recover from Time Machine Backup‘ and click ‘Continue.’
4. Click ‘Continue‘ again.
5. Choose a Time Machine backup before installing the version of macOS you want to get rid of and click ‘Continue.’
Remember that if you recover an old backup, you will lose all the data added since you upgraded your Mac to the version of macOS that you now want to uninstall.
How to get back to the operating system that came installed on your Mac
Now that we’re talking about the concept of ‘Recovery,’ you might want to go back to the version of macOS that the Mac came with when you bought it.
It didn’t work for us, perhaps because the internet connection wasn’t perfect, but theoretically, it should work!
With macOS Sierra 10.12.4, this feature was introduced in macOS ‘Recovery .’ It should reinstall the version of the macOS you purchased your Mac with. Or at the very least, so Apple says.
The company says you should turn off your Mac, and then while restarting it, press ‘Shift + Option/Alt + Command + R‘ at the same time. You will surely need to use both hands.
Note that if you have a Mac with M1, this process has changed. However, being such a new device, you won’t be able to install any version of macOS earlier than Big Sur.
Here are the steps Apple says:
1. Launch your Mac and press ‘Shift + Option/Alt + Command + R’.
2. Once you see the macOS ‘Utilities‘ window, choose the ‘Reinstall macOS‘ option.
3. Click ‘Continue‘ and follow the on-screen instructions.
4. Select a bootable disk and click ‘Install.’
5. Your Mac should restart once the installation is complete.
Important: This will erase your entire Mac, so copy what you want to keep before performing this process. Here is a guide you can use: How to Backup a Mac in Simple Steps
How to install an old macOS from a boot installer
This process is known as “clean installation,” which we talked about in more detail in our article How to Do a Clean Installation of macOS. In this case, you’ll reset your Mac and install the version of macOS you want from scratch.
1. Download the installer for the version of macOS you want to install from the Mac App Store. Again, visit our article How to get older versions of macOS to learn how.
2. Use the installation file to create a boot installer on an external storage device. For more information, visit How to Create a Bootable USB to Install macOS.
3. Next, you will need to delete all data from your Mac by restoring it to factory settings. To do so, restart your Mac in Recovery Mode and press the ‘Command + R’ keys at the same time when booting.
4. Your Mac will open ‘Disk Utility.’ Click on ‘Disk Utility,’ followed by ‘Continue.’
5. Select the main volume and click ‘Unmount,’ followed by ‘Delete.’
6. Close ‘Disk Utility.’
7. Now, click on ‘Reinstall macOS‘ and hit ‘Continue.’ Follow the instructions to reinstall macOS using the installer you just saved to your external drive.
How to run an old macOS on an external drive
Running a macOS version on an external drive is a good option if you intend to continue using the version of macOS currently installed on your Mac.
It is possible to run a version of macOS or Mac OS X from an external storage device connected to your Mac. To know how to do it, we recommend reading our article How to install macOS on an external hard drive.
Once you have installed macOS on an external disk, press the ‘Option/Alt’ key when starting your Mac and choose which to boot from that disk.
The advantage of using this method is that you won’t need to reset your Mac. On the other hand, the big drawback is that the old version of macOS may work a bit slow (especially if it’s a slow USB).
How to install an older Mac OS X on a virtual machine
Before explaining how to install a version of Mac OS X on a virtual machine, it’s essential to look at Apple’s terms and conditions of use.
Since Mac OS X 10.7, Mac operating system versions can only run in a virtual machine if the Mac in question uses the same version.
That means installing an OS X 10.8 virtual machine on a Mac with another version of OS X is a violation of the 10.8 software license agreement.
The newest version of OS X that legally allows it to run on a virtual machine from a different OS X Mac is Snow Leopard (10.6).
In these cases, the solution is to run the server versions of the OS you need, as long as you have obtained the Apple software license. Despite that, both VMware Fusion and Parallels support both versions.
Another element to keep in mind is that Apple’s usage agreement does allow mac os to run on two virtual machines on the same computer. Still, these virtual machines can only be used personally (unless you are registered as an Apple developer).
It would be best if you also kept in mind that, as we have said before, Macs cannot use a version of OS X earlier than the one they had installed when they arrived on the market, even from a virtual machine. If you want to use an older version of OS X, you’ll need to get an older Mac.
I hope this guide on How to install older versions of macOS or Mac OS X was easy. If you face any issues, please comment below.