Install macOS on Unsupported Macs - Catalina/ Big Sur/ Monetery/ Ventura and Sonoma

From a security standpoint, using the latest version of macOS — the Mac operating system — is essential, especially if you want to stay safe from actively exploited vulnerabilities. While almost all Macs since 2010 can run the latest macOS, Apple keeps you from enjoying them unless you buy their latest and greatest.

Apple drops support for Mac models that it declares to be vintage or obsolete.

If you wish to use the latest version of macOS but Apple no longer supports your Mac, the best option (in terms of speed, system stability, and the full range of Apple features) is to simply buy a new Mac. Of course, not everyone can necessarily afford to do so.

But what if there were a way to continue running the newest and safest version of macOS for much longer than Apple is willing to support your Mac model?

There’s hope for older Macs

There is, in fact, hope for users of many old Mac models. With a bit of effort, you can use a source-available, third-party utility that makes it possible for you to run the latest macOS version on significantly older hardware, with (for the most part) relatively minimal caveats.

The newest Mac operating system is macOS Sonoma. Following is the complete list of Apple’s supported models for macOS Sonoma (14.x):

MacBook Air (2018 or newer)
MacBook Pro (2018 or newer)
iMac (2019 or newer)
iMac Pro (2017)
Mac mini (2018 or newer)
Mac Pro (2019 or newer)
Mac Studio (2022 or newer)

The list of additional Macs that can currently run macOS Sonoma — unofficially (we’ll explain what that means later), includes some much older models, as follows:

MacBook (Late 2008 through 2017)
MacBook Air (Late 2008 through 2017)
MacBook Pro (Early 2008 through 2017)
iMac (Mid 2007, after upgrading the CPU)*
iMac (Early 2008 through 2017)
Mac mini (Early 2009 through Mid 2014)
Mac Pro (Early 2008 through Late 2013)
Xserve (Early 2008 and Early 2009)

*The mid-2007 iMac requires a processor upgrade (not for the faint of heart). But incredibly, this computer that is now nearly sixteen years old can still run macOS Sonoma.

Those unofficial lists look a lot better than Apple’s official support list, right? Perhaps it seems too good to be true, and to be fair, there are some known issues with some of those models (see the OpenCore Legacy Patcher supported models list for details).

You might be wondering how such a thing could possibly work. In part, it uses a similar methodology to so-called “hackintosh” computers, where additional Apple drivers from previous versions of the operating system are included to make the current version of macOS work with a wider range of hardware.

Apple may not want to exert the effort to keep the latest macOS working on your old Mac hardware. (This actually makes a lot of sense, especially when you consider that Apple makes money by selling new Macs and doesn’t directly profit from macOS upgrades.) But thankfully, a handful of hobbyists are willing to pour a lot of hours into making new macOS versions work on older Macs without any support from Apple.

Preparing to patch

If you want to run macOS Sonoma or Monterey, but can’t due to your Mac not being officially supported, here is how to go about it:

1. First, go to your Apple menu and select “About This Mac.” Write down what it says next to “Model” (if it’s listed). Then click on “System Report…” (or “More Info…”). In the hardware overview window that pops up, a “Model Identifier” will be listed; write this down as well.
2. Now that you’ve confirmed your Mac model, next you’ll need to verify that OpenCore Legacy Patcher works with your Mac by reviewing the supported models list.
3. Back up all your data. Use Apple’s Time Machine and/or Intego Personal Backup, follow a “3–2–1” backup strategy, and ensure that your backups are really working.
4. Grab a USB flash drive (or any USB/FireWire/Thunderbolt external hard drive) that can be erased and is 16 GB or larger in size. (Ideally, choose a fast external drive. This will save time when copying the macOS installer to the drive and booting your Mac from it during installation.)
5. Download the latest version of OpenCore Legacy Patcher from this site. Be sure to choose the “GUI” version that’s several hundred megabytes.
6. If you normally use a Bluetooth wireless keyboard and/or mouse, it’s ideal to instead use a wired USB keyboard and mouse for this process. (If you’re upgrading a MacBook, the built-in keyboard and trackpad are fine, in most cases.)

As an aside, you can find many of the steps from this guide (and a few additional details) on the OpenCore Legacy Patcher site. But I’ll take the journey with you using my iMac (20-inch, Mid 2007, with an upgraded CPU) and add some helpful tips based on my experience. Mine is the oldest supported (er, unsupported) model, and it’s ten years older than the minimum iMac model that Apple still supports. (Note that I’m upgrading from a patched version of Catalina, but the steps below are the same regardless. The screenshot below is actually from another Mac running OS X El Capitan 10.11.6, which happens to be the final macOS version that Apple supported on my iMac, too.)

Although hardware upgrades are not usually required, you may wish to upgrade your Mac to the maximum amount of RAM and replace your hard drive with a solid state drive (SSD), assuming your Mac model is user-serviceable and you’re comfortable doing such upgrades. This will make your machine run much smoother.

Of course, it probably goes without saying, but Intego cannot provide technical support if something goes wrong. Proceed at your own risk.

Now that you’ve got everything ready to go, let’s begin!

How to install macOS Sonoma on an unsupported Mac

Note: This step-by-step guide was originally written for macOS Monterey, but it should still apply to macOS Sonoma as well. See the section Is macOS Sonoma supported? for additional details about Sonoma.

Having completed all your prep work from the previous section, now you can follow this step-by-step guide to installing macOS Sonoma on your unsupported Mac.

1. Plug in your USB flash drive or external hard drive. (You’ll need this for later steps.)
2. Open the “OpenCore-Patcher” app (the GUI-Offline version that you downloaded in step 5 of your preparation). Click “Open” if prompted.

1. In the app’s main window, click on the “Create macOS Installer” button.

1. Choose the option to “Download macOS Installer” (unless you’ve recently downloaded one). A new window will appear listing available macOS versions. Click on the most recent non-beta version, which should appear near the bottom of the list.

1. The macOS version you selected will begin to download. When the download finishes, you may be prompted to enter an administrator’s username and password “to add InstallAssistant” for the next step (this copies the “Install macOS Sonoma” app to your Applications folder).
2. Next, click on the “Flash Installer” button. You’ll then be prompted to choose the “Install macOS Sonoma” app that you downloaded in the previous step. (If you have multiple options, choose the most recent version of Sonoma in the list.)

1. You’ll then be prompted to choose your USB flash drive or external hard drive. (If you have multiple options to choose from, select carefully; the next step will completely erase the drive.) You may wish to write down the disk details; you’ll need to choose the same disk again later.

1. Again, you may be prompted to enter an administrator’s username and password because “OCLP-Helper wants to make changes” (OCLP is short for OpenCore Legacy Patcher; this step allows for your external drive to be formatted).
   As explained on the “Creating Installer” screen, the process of copying data to your external drive can potentially take a very long time; this step took almost 90 minutes on my 2007 iMac.

1. Once that process is complete, you’ll get a “Success” dialog box, and then you can click on the “Return to Main Menu” button.
2. At the “main menu” window, click on the “Build and Install OpenCore” button.
   A new window will appear; click on the “Build OpenCore” button to continue.

1. Once the text stops scrolling, the “Build OpenCore” button will change to say “Install OpenCore” instead; click on Install OpenCore.

1. In the “Install OpenCore” window, click on the button for the same disk that you chose in step 7 above (i.e. your external drive).

1. Next you’ll need to choose the partition. There should only be one button in this list (it will probably say “EFI” in the middle). Click on that button to continue.

1. Again, you may be prompted to enter an administrator’s username and password because “OpenCore Legacy Patcher needs administrator privileges to mount your EFI.” This is necessary to prepare the external drive for the next steps.
2. Moments later, you’ll see a bit of text, ending in “OpenCore transfer complete.” Your Mac is now ready to install macOS Sonoma.

1. Now it’s time to install the new OS on your Mac! Read this entire step carefully before you proceed; you’ll need to be ready to press buttons on the keyboard quickly. Click on the Apple menu, then select “Restart…” and click Restart again when ready. Immediately begin holding down the Option key on your keyboard (or “Alt” if you’re using a third-party USB keyboard). Immediately as soon as you see multiple drive options, stop holding the Option/Alt key, and use the arrow keys to choose the “EFI Boot” option with the blue-and-white OpenCore logo. Press the Return or Enter key to select this option.

1. Next, use the arrow keys and Return/Enter to select the “Install macOS Sonoma” option.

1. Your Mac will start booting up from the installation disk. Depending on the age and speed of your Mac and your external drive, this may take a few minutes.
2. Once your Mac finishes booting, you should see the following options: Restore from Time Machine, Install macOS Sonoma, Safari, and Disk Utility.

1. Choose “Install macOS Sonoma” and let the installer run as normal. In the pane where you’re prompted to select a disk, be sure to choose your Mac’s internal drive (e.g. “Macintosh HD”).
2. After a while, your Mac will probably restart on its own. If it brings you back to the screen shown in step 17, just click on the Apple menu and select Restart, and immediately begin holding Option again. Select “EFI Boot” again, but this time you’ll need to choose the “macOS Installer” option with the internal hard drive icon superimposed (pictured below). This will allow the operating system installation to complete.

1. When macOS Sonoma has finished installing, there are just a few more steps remaining. First, you’ll want to set up your internal drive properly to ensure you no longer need the external drive attached. To do this, open the OpenCore-Patcher app (the one you used in step 2). From the main menu (as depicted in step 3), repeat steps 10 and 11 again to build and begin installing OpenCore.
2. Although in step 12 you chose your external drive, this time you’ll instead select your internal drive (which is most likely disk0, but may vary depending on your Mac).

1. Like step 13, there should only be one option that says “EFI” near the middle; click this button.
2. Like step 14, you’ll prompted to enter an administrator’s username and password because “OpenCore Legacy Patcher needs administrator privileges to mount your EFI.” This is necessary to prepare the internal drive to boot without the external drive attached.
3. Once you see a window similar to step 15, again you’ll see a bit of text ending in “OpenCore transfer complete.” Click on “Return to Main Menu” to prepare for the next step.
4. From the main menu, click on the “Post Install Root Patch” button. (This will help you install any additional fixes that may be necessary to make Sonoma work with your Mac’s legacy hardware.) Then click on the “Start Root Patching” button.

1. When you receive the “Relaunch as root?” prompt, click Yes. Again you’ll be prompted for an administrator’s username and password, because “OpenCore Legacy Patcher needs administrator privileges to relaunch as admin.” The app will relaunch at the main menu, at which point you should repeat step 24. Then proceed to step 26.
2. Once it says, “Patching complete,” you’ll also see the message, “Please reboot the machine for patches to take effect.” Before you reboot, drag your external (e.g. USB) drive’s icon from the desktop to the Trash to eject it, and then physically unplug the external drive from your Mac. Then click on the Apple menu, click “Restart…” and then click Restart. Hold Option/Alt one more time, and select the internal drive’s EFI Boot option.

You’re all set! Your Apple-unsupported Mac is now running macOS Sonoma!

Installing macOS updates (minor and major)

The next time there’s a minor macOS update, i.e. a new version of Sonoma, here’s what to do to ensure everything goes smoothly:

1. Back up important files from your computer. (Refer to step 3 in the “Preparing to patch” section of this article for tips.) You should do this anyway, regardless of whether you’re using a Mac that’s supported or not.
2. Run the OpenCore-Patcher app to check for updates. If it informs you that an update is available, download the GUI-Offline version.
3. Most of the time, you may be able to install minor macOS Sonoma updates like normal.

• Sonoma updates might occasionally include significant changes that may require an OCLP update first. You may want to wait a day or two after Apple releases a new Sonoma update, and check OCLP’s known issues page, before installing Sonoma updates. You can get the latest Sonoma update via Apple menu > System Settings > General > Software Update.

1. After installing a Sonoma update, your Mac will reboot automatically. After you log in, you’ll need to reinstall the Post Install Root Patch (steps 24 and 25 above), and then restart your Mac again.

Before you consider upgrading to a major new macOS version (like whatever Apple decides to call “macOS 15” in late 2024), you’ll need to wait to ensure OCLP is compatible first. An update to OCLP is always required before you can safely upgrade to the next major macOS version. (If you want to upgrade from Ventura or older to Sonoma, see the section “Is macOS Sonoma supported?“)

If the installation was successful and you’re thrilled to be able to run the latest operating system on your old Mac hardware, consider offering to donate old Mac hardware to the OpenCore Legacy Patcher developers. (Or, if you prefer, the project also accepts financial contributions that may be used toward purchasing hardware.) This will help the OCLP team test updates more quickly and thoroughly on a wider variety of older Macs.

Additional tips

Now that you’re using macOS Sonoma on an unsupported Mac model, here are a few more things you might like to know:

• Back up your important files often. Not only are you running macOS in an unsupported manner, but your hardware is also quite old, so there is an increased risk of data loss. To keep your documents safe, you can use Apple’s Time Machine and/or Intego Personal Backup, use a 3–2–1 strategy, and confirm that your backups actually work.
• Keep the external drive handy that you used to install Sonoma. You will need it for installing future major macOS updates, like macOS 15 (assuming, of course, that your Mac will be “unofficially compatible” with it).
• Another way to stay aware of OpenCore Legacy Patcher software updates is to subscribe to Mr. Macintosh on YouTube. He releases a video for each new OCLP update and macOS update, so if you have any concerns about the process or want to be sure there aren’t any “gotchas” before you update, this is a good way to keep informed.

Welcome to the legacy patching community!

Congratulations! Your older Mac will now be able to keep up with the latest security updates. Although firmware updates are not included (those are model-specific, and Apple only releases them for supported Macs), your macOS will nevertheless be much more secure than it was with the old version of Mac OS X you were running before.

Every time a new macOS is released, I look forward to the next macOS patcher, as it keeps our beloved — and still more than capable — old Macs around for just a while longer.

Is macOS Sonoma supported?

Apple’s latest Mac operating system, macOS Sonoma, is officially available to the public as of September 26, 2023. (Learn more about macOS Sonoma’s top 10 new features and notable security improvements.)

As usual with new macOS versions, macOS Sonoma eliminates support for several Mac models. The following models that Apple officially supported for macOS Ventura are not officially supported for macOS Sonoma:

• iMac (2017), which Apple sold new until 10/2021
• MacBook (2017), which Apple sold new until 7/2019
• MacBook Pro (2017), which Apple sold new until 7/2019

The team behind OpenCore Legacy Patcher worked with macOS Sonoma betas for months to resolve newly introduced compatibility issues. On October 2, 2023, the OCLP team released version 1.0.0, bringing Apple’s macOS Sonoma to these now-unsupported Macs, as well as to the previous Macs that could (unofficially) run macOS Ventura.

Download the latest version of OCLP, check their GitHub releases page.