macOS Catalina 10.15 was released to the public just a few days ago. It is available with a number of new features and updates. Unfortunately, not all users who had macOS Mojave installed on their Macs will be able to upgrade to Apple's latest desktop operating system. Apple's reason for this is that older Macs do not have Metal-capable graphics processors. No matter how you feel about this, the result is that users with older Macs don’t get to experience the bells and whistles of macOS Catalina, officially. We say officially, because there is an unofficial method of installing macOS Catalina on unsupported Macs. Follow our step-by-step guide to find it how.
Install macOS Catalina on an unsupported Mac
Before we start, make sure that you have:
- Access to a Mac which can be used to download and create a bootable USB installation drive.
- The drive would need to be at least 16GB in size and formatted in Mac OS Extended (Journaled) format.
- Backed up the data on your Mac where you want to install Catalina.
Lastly, note that this process relies on patches and hacks, and you might still face issues with running macOS Catalina without any bugs on your unsupported Mac.
Officially, macOS Catalina is only supported on the following Mac models, since they have graphics processors with support for Metal, Apple's graphics API.
- MacBook (Early 2015 or newer)
- MacBook Air (Mid 2012 or newer)
- MacBook Pro (Mid 2012 or newer)
- Mac mini (Late 2012 or newer)
- iMac (Late 2012 or newer)
- iMac Pro (2017)
- Mac Pro (Late 2013 or newer)
Thanks to macOS Catalina Patcher tool, you can install the operating system on the follow Macs:
- Early-2008 or newer Mac Pro, iMac, or MacBook Pro
- Late-2008 or newer MacBook Air or Aluminum Unibody MacBook
- Early-2009 or newer Mac Mini or white MacBook
- Early-2008 or newer Xserve
However, the following Macs are not supported, even by the Patcher tool:
- 2006-2007 Mac Pros, iMacs, MacBook Pros, and Mac Minis
- 2006-2008 MacBooks
- 2008 MacBook Air
Create Patched macOS Catalina USB Installer
Once you have checked if your Mac is supported, follow the next steps:
- Download the latest version of the macOS Catalina Patcher from here. Always download the latest version since the developer continues to update the app with the latest patches and fixes.
- Run the app and click Continue.
- On the next screen, click on 'Download a Copy'. We will use this option because we will create a bootable USB drive installer.
- The installer is around 8GB in size so it might take a while for the download to complete.
- Once done, you will be given a choice of installation method. Here, plugin in the USB flash drive and click on 'Create a bootable installer'.
- Once the drive is created, plugin into your unsupported Mac where you want to install macOS Catalina on. Turn on the Mac and hold down the Option key. You will see the Startup Manager. Use arrow keys to select the bootable USB drive and hit Return.
- When you are booted into the macOS Recovery environment, make sure to format your internal drive, where you will install macOS Catalina, to APFS using Disk Utility. This step is required if you are updating from a very old version of macOS which did not support APFS.
- Next step would be to use the Reinstall macOS option to start the installation process. Let the install process complete. You might see some command line messages during the process. These are completely normal, and part of installation process created by the developer, to ensure compatibility.
- Once installation is complete, shut down the Mac, and reboot it using the USB drive again. The reason for doing this is so that post-install patches can be applied, to make sure that Catalina works fine on your system.
- When you are back in the macOS Recovery environment, click on the option which says 'macOS Post Install'. By default, the installer will select all the right patches required for your Mac. Click Apply Patches and allow the process to complete.
- After the patches are applied, select the option which says `Force Cache Rebuild`, and click Restart.
- Your Mac will restart, and you should be able to setup macOS Catalina.
Let us know how the process works for you. Have you gotten Catalina successfully installed and working on an old Mac?