Moving to Catalina: Keep Your 32-Bit Mac Apps Running with Parallels

Originally published at:

While macOS 10.15 Catalina won’t support old 32-bit apps, you can keep them running indefinitely on your Mac by installing a copy of 10.14 Mojave in a Parallels Desktop virtual machine.

I wish I could run Snow Leopard in Virtual PC so I could use Rosetta for PPC apps.

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A post was merged into an existing topic: Nonstop whining about how Apple sucks

You might be able to run Snow Leopard in an older version of Parallels or maybe in this version? But then you’d have to virtualize an older version of Parallels inside a newer version.

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I ran into a snag with the process described in the article: The App
Store won’t let me download a Mojave installer because it’s not
supported on my current machine (a 2010 17-inch MBP). I’m expecting to
replace this machine with one of the new 16-inch MBPs that are expected
to come out this year, if it will meet my needs, but it’s pretty much
guaranteed that those machines will come with Catalina pre-installed.

I still have a High Sierra installer (the most recent macOS version
supported on my MBP), but I’d prefer to be able to run Mojave in a VM,
for the exact reasons Glenn gives in the article. Is there a reasonable
way I can get a Mojave installer now, without having access to a machine
that can run Mojave?

Mark D. McKean

Oh, that is an interesting edge case. There are some paths you can use to download stuff from Apple sometimes (you have to know a very particular web address), but this failed for me recently. I think you’re going to need to find a buddy with Mojave installed and bring an 8GB or 16GB memory stick.

The installer should not be registered to the App Store the way other apps are, as I recall, because it has to run when you don’t necessarily have an Internet connection.

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Thank you for this detailed advice, which I will keep handy but…

“It makes sense to use Mojave, rather than an earlier macOS release, because Mojave will receive security updates longer than older versions of the operating system…”
So I may as well stick with Mojave until security updates cease and refuse the “upgrade” to Catalina so that my legacy 32-bit apps will still run with ease.

One issue will be if I have to replace a Mac because the new one will come with Catalina. Will the Mojave download tip work for a new Mac (i.e. replace Catalina with Mojave)?

I have an old version of Parallels that I sometimes use for running old Windows programs but I would not like to have to use it on a regular basis or pay for frequent updates that I don’t need.

Complicated to answer. Software will increasingly be updated to only be compatible with later releases of macOS, so I was seeing this as a divergence. You keep the Parallels environment to keep 32-bit apps (but maybe also as a backup for 64-bit apps that no longer run in future macOS?) and you can keep your main system running with all the security and integrity of newer releases.

I have done this with Tiger (10.6 from Apple support macOS archive), the last macOS to support Rosetta.

I use the latest version of Parallels. ask Parallels support.

Glenn Fleishman

    September 18

wish I could run Snow Leopard in Virtual PC so I could use Rosetta for PPC apps.

You might be able to run Snow Leopard in an older version of Parallels or maybe in this version? But then you’d have to virtualize an older version of Parallels inside a newer version.

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Is it possible to make a Parallels virtual machine copy of my current Mojave installation, then prune it down, keeping selected 32-bit apps, to run only 32-bit apps?

If you run Parallels Mojave on Catalina in Coherence mode, you might not even notice the difference.

Yep, that’s always possible, for some period of time. But at some point, something will force you to upgrade, and the longer you wait, the more unpleasant that process will be. Needing a new Mac, as you suggest, is a big one, but you might also want to take advantage of a compelling new feature in some app you rely on. Or you might need to maintain compatibility with a future version of iOS.

It depends on what Mac you buy. If you get a model that could have worked with Mojave, yes, you’ll probably be able to download Mojave. However, if you get a newer Mac model released only after Catalina ships, such as the rumored 16-inch MacBook Pro mentioned above, that very well may not allow you to download Mojave.

Seems to me that you’d have to pay for one update that you did need to get Catalina compatibility, but nothing more. That doesn’t seem unreasonable—software companies can’t be faulted for their older apps not being compatible with future operating systems.

(for Glenn) I like Address Labels ($6.99, App Store, 64 bit) much better than Addresses&Labels, and it has an IOS version, too. It’s by Nigel Hamilton - - who readily addresses problems.

I’m interested in this as well. While I like Glenn’s approach with a clean install, you can imagine situations where it might just be simpler to take a clone of an existing install and turn that into a virtual macOS.

I realize you could go Glenn’s route and then use Migration Assistant from within the VM to achieve that, but I’d be more curious to hear about a direct path from clone to VM.

The rule of thumb here is that a Mac will work on whatever it originally shipped with. Any Macs selling now runs Mojave so they should continue to run Mojave even if you buy it when it comes with a preloaded version of Catalina. However, a Mac launched in say November will most likely ship from the start with Catalina and will NOT run Mojave.

I haven’t tried this, but when you set up Mojave from scratch in the virtual machine, couldn’t you just migrate your existing system from Time Machine or a bootable duplicate? It would have a vast amount of unnecessary cruft, so you’d need a LOT of disk space, but I don’t see why it wouldn’t work.

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Isn’t another solution to create a bootable back up with SuperDuper or such, then boot from there where you need to? I think this will only work if you currently have a machine that can boot from an pre-Catalina systems, but it could be a path for those not wanting to buy a new Catalina machine. And, of course, you can keep your older machine running for the times you need the 32-bit applications.

Jack Clay

I got to thinking about that, and remembered I had gotten a link last
year, when Mojave had come out, to a utility that was supposed to allow
installing Mojave on unsupported hardware. I never actually tried it,
but I found that I had saved the link. I may have even gotten it from
someone here.

I checked the page, and found that the utility can directly download the
Mojave installer. I just tried it, and it downloaded what appears to be
a fully functional Mojave installer. It won’t run on my machine without
the utility patching it, of course, and I don’t want to patch it for
running on a VM on a newer (supported) machine.

Does anyone know a way that I can verify that this installer is legit
(like a checksum, or knowledge of the person who made the utility, or
such) without running it?

Mark D. McKean

You can definitely essentially image your current system and run it in Parallels, but I agree with Adam — it’s better to start from scratch and migrate, as it will save you problems down the road.

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Looks slick and ridiculously affordable. I will give it a try!

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Definitely. The utility of Parallels Desktop is to be able to spin up the environment quickly and to run it simultaneously. I think if you need a full environment to work in, then it’s for sure sensible to have a drive you can boot into on a machine that can still run that version of macOS.

This does also future proof you. You can run this virtual machine until this and presumably all future versions of Parallels, which is kind of slick. So you could run Mojave in 10 years if you really needed to. Archivists (like, ahem, one TidBITS Publisher’s parent) probably love this to pieces in terms of keeping old stuff at least feasibly accessible.