With the arrival of macOS Catalina, Apple's transition towards 64-bit technology is complete. Starting with macOS Catalina, 32-bit apps no work on your computer. With that being said, there are some workarounds to consider if you happen to have older software that's essential for work or play. Think VM!
Do this first
Before doing anything else, you should check with the app developer to see if a 64-bit version of your software title is available. The transition to 64-bit technology was a lengthy one for Apple and the odds are high that your developer did make the switch.
Do you have 32-bit apps installed on your system?
Moving on, you can confirm whether you have 32-bit apps on your Mac by:
- Choose the Apple icon on the Mac toolbar.
- Click About This Mac.
- Select System Report.
- Select Legacy Software in the sidebar. All legacy software is 32-bit.
Use virtualization to run your old apps
Here's a look at the best ways to run older software on your Mac.
Running older software
The issue with running old versions of software is that it can eventually "break" and not function on a future version of the OS you are running it on. You can hope that the vendor of your application will keep on updating the software to run on future OS updates, but what if you have a very specific program that is no longer maintained? Or perhaps you have a software license for your current version of an application but upgrading to a more modern version introduces too great a cost?
Running a virtual machine
One possible solution to the 32-bit application dilemma is to run a version of the latest macOS that fully supports your app in a virtual machine. A virtual machine, or VM, is an emulated computer running on top of your current OS installation as a program. The VM takes resources from your actual computer and uses them to run itself in a contained environment as a separate system altogether. Think of it like the Matrix where the real world is your physical computer and the "dream" world in the VM.
Benefits of a VM
Since you needn't buy new hardware, you can simply run an instance of the macOS version that will run your application without issue regardless of that app being 32 bit or 64 bit for as long as you keep your VM. If you upgrade the macOS on your physical Mac, the VM version is completely separate from that process so you'll still be able to keep the "old" macOS on the VM and run the "new" macOS for all of your other up-to-date programs. You'll be able to have your proverbial cake and eat it too.
Setting up a VM
There are a few options for VM software solutions for you to choose from. You can run Virtualbox, VMware (opens in new tab), QEMU, and Parallels (opens in new tab). All of the non-open source VM managers have free "lighter" versions that will serve our purpose but you can get their full fledge versions that provide various features that are beyond the scope of this article.
We will be using Parallels Lite (opens in new tab) that is freely downloadable from the App Store. We chose Parallels Lite due to their ease of setup and ability to function on top of a macOS host passing system information that is needed for the guest macOS to properly install. Note that if one day you'd want to change your Mac's operating system to Windows or Linux then you'd might want to install one of the other mentioned VM managers since those can run on those host OSs albeit with a much more involved setup.
We will also be using macOS High Sierra (opens in new tab) as the installed OS. You can use these instructions for older versions as well. Credit to Howtogeek.com for the command line bits to make a disk image to install macOS High Sierra from their Virtualbox install instructions on Windows 10.
- Download Parallels Lite (opens in new tab) from the App Store.
- Download (but do not install) macOS High Sierra (opens in new tab).
- We need to create the install image so we need to start Terminal.
- In Terminal in your home directory type or copy and paste line by line the following:
- hdiutil create -o HighSierra.cdr -size 7316m -layout SPUD -fs HFS+J
- hdiutil attach HighSierra.cdr.dmg -noverify -nobrowse -mountpoint /Volumes/install_build
- asr restore -source /Applications/Install\ macOS\ High\ Sierra.app/Contents/SharedSupport/BaseSystem.dmg -target /Volumes/install_build -noprompt -noverify -erase
- hdiutil detach /Volumes/OS\ X\ Base\ System
- hdiutil convert HighSierra.cdr.dmg -format UDTO -o HighSierra.iso
- mv HighSierra.iso.cdr HighSierra.iso
- Start Parallels Lite.
- Select Linux only.
- Click Continue.
- Select Install Windows or another OS from a DVD or image file.
- Click Continue.
- Select Image File.
- Click Select a file.
- Navigate to your home directory and select the HighSierra.iso file we created in terminal.
- Click Open.
- Click Continue.
- Select macOS as the operating system type.
- Click OK.
- Navigate to the folder to house the VM.
- Click Select.
- Name your VM and click Create.
- You can optionally set up any VM options you desire such as (note that these can be changed later too):
- Startup and sharing settings in the Options tab.
- Choose CPU, memory and graphic options in the Hardware tab.
- Still under the Hardware Tab select the CD/DVD sub-option.
- Click the dropdown arrow for Source.
- Select Chose an Image File.
- Navigate to your home folder and select the HighSierra.iso file we created in terminal.
- Select Open.
- Select Continue.
- You can now Start the VM.
- Install macOS like you would normally do on any real system
Once you have a completed install, you'll want to install the Parallels Tools program in your VM macOS. This will allow you to be able to seamlessly use your mouse between your real desktop and your VM desktop as well as resize your VM screen on the fly with proper display attributes.
- Click the highlighted yellow exclamation point over your VM window.
- Click Continue.
- On your VM, double-click the Parallels Tools installer that opens.
- Complete the installation and reboot your VM.
You now have a full-fledged macOS installation that you can keep for your older 32-bit applications once macOS decides to give them the boot. You'll be able to make snapshots of the VM to have different save states. You'll be able to run all native macOS applications you normally do. The drawback will be the speed of execution and disk speed but if you have a powerful Mac, you may not notice too much of a difference depending on the application. Does this solution work for you? Tell us what you'd rather see happen for 32-bit applications on macOS in the comments!
Bryan M. Wolfe has written about technology for over a decade on various websites, including TechRadar, AppAdvice, and many more. Before this, he worked in the technology field across different industries, including healthcare and education. He’s currently iMore’s lead on all things Mac and macOS, although he also loves covering iPhone, iPad, and Apple Watch. Bryan enjoys watching his favorite sports teams, traveling, and driving around his teenage daughter to her latest stage show, audition, or school event in his spare time. He also keeps busy walking his black and white cocker spaniel, Izzy, and trying new coffees and liquid grapes.