How to run Photoshop CS5.1 on MacBook Pro M1 Pro and Mac mini 2024 M4 with High Sierra using a portable drive?

As far as I know, all one-time-purchase versions of Photoshop use 32-bit installation and activation code. So even though the main Photoshop CS 5.1 application is 64-bit, there's no way to install and run it on any Intel-based Mac running Catalina or later, or on any Apple-Silicon-based Mac.

An external boot drive containing High Sierra won't help you, as no Apple-Silicon-based Mac will be able to start up from it.

VikingOSX wrote:

no Intel compiled software binaries are supported on any Apple Silicon (M1 - M5) Mac architecture.

Rosetta 2 lets you run some Intel-compiled software binaries on Apple Silicon Macs. However, Rosetta 2 has limitations.

• It doesn't support system-level code, like Intel-only operating systems and kernel extensions.
• It doesn't support 32-bit code.
• It doesn't support instructions needed to create Intel virtual machines.

So Rosetta 2 wouldn't be able to run the installation and activation code for Photoshop CS 5.1, or to run High Sierra.

You cannot run 32-bit software on any version of macOS after macOS Mojave (10.14) and no Intel compiled software binaries are supported on any Apple Silicon (M1 - M5) Mac architecture.

F1Vanc wrote:

Thank everyone for the information. I suppose I'll have to come up with a "planB"!

One plan B might be to get an old Mac that can run High Sierra and install Photoshop CS5.1 to that and use it as a dedicated Photoshop Mac.

But beware that Adobe has shut down license servers or made activating at least later versions like Photoshop CS6 difficult. I don't know if earlier versions suffer from that or if they can be installed completely offline.

I occasionally dual boot my Mac mini 2018 from Sequoia to Mojave or Mac OS X Server Server 10.6.3 virtual machine to run old 32-bit apps like Photoshop CS6 13.0.0, Lightroom 6.14, MPEG Streamclip 1.9.3b8, QuickTime Player 7 Pro, (and just for nostalgia MT-NewsWatcher 3.5.3b3 via Snow Leopard's PowerPC emulation).

Plan B and C might be to just install the free forever Affinity Studio that will work fine on your M4 Mac Mini. Canva is purely optional. The Affinity app can read and export Photoshop and Illustrator files.

A good Plan B would the free Affinity Photo which is bundled with Affinity Designer and Affinity Publisher.

I used to use Photoshop CS5 and when it became too old switched to Photoshop Elements 2025 which is a one time purchase for 3 years of updates. It could do everything I did with PS except save as a CMYK color profile.

However, I've tried Affinity and find it to do everything I want it to do and the price is right.

👍

Oh to be 84 again.

I'm having to learn how to use Numbers for data records as I'm going on to Tahoe after the first of the year and my FileMaker Pro will no longer work.

Servant of Cats wrote:

• It doesn't support 32-bit code.

I guess you missed the first part of Viking's post…

"You cannot run 32-bit software on any version of macOS after macOS Mojave (10.14)"