After a recent MacOS update, I am no longer able to run the (latest) AxoGraph software for electrophysiology data analysis on my computer, as I get the following error message:

"AxoGraph.app" needs to be updated.

The developer of this app needs to update it to work
with this version of macOS. Contact the developer for
more information.

Screenshot: enter image description here

I understand that this is because AxoGraph is a 32-bit application, which is not supported by macOS Catalina. I have already contacted the support of the application for advice. In the meantime, is there any good solution besides switching to a different software?

  • 1
    $\begingroup$ I don't have a good solution for you, but in solidarity, I would note that I still have a (network-isolated) machine running Windows XP due to the lack of a software update for my patch clamp hardware (and lack of success running in any sort of 'compatibility mode'). I hope you can find a solution! $\endgroup$
    – Bryan Krause
    Dec 19, 2019 at 16:41

1 Answer 1


Response from AxoGraph Support

I received an answer from John of AxoGraph suggesting to follow the steps outlined in this tutorial to set up a virtual machine (VM) on my computer with an earlier version of macOS using the Parallels software ($79.99/year).

He also discouraged using VirtualBox, the free VM manager, as "there's more work involved, and it’s not so smoothly integrated with Catalina." In his reply, John also promised "to finish the new completely re-written 64-bit version of AxoGraph," which "is not far from completion," first releasing a new data-acquisition-only version, subsequently followed by an update with data analysis features. It sounded like all of this would take at least several months, though.

My Solution

After some digging, setting up a virtual machine (VM) with an earlier version of macOS indeed did seem to be the best option for me at this point. What I was after, however, was a free solution - and eventually, I managed to get a Mojave VM to work on my Catalina using VirtualBox. Getting through the whole process was a patchwork of several different sources (mostly following this tutorial and its comments), so I decided to re-write the detailed steps I took below (some steps may be adjustable but I used these specific settings with success):

1. Download macOS Mojave Installer:

  1. Go to this link: https://support.apple.com/en-us/HT210190
  2. Click on Get macOS Mojave in step 4, and open in App Store.
  3. Click on GET - that will open the updater, which will download the installer (if you already have Catalina installed, the "update" will stall after the download automatically)
  4. Find it in your Applications folder as Install macOS Mojave.app

2. Create an ISO installation media using Terminal:

  1. Create a temporary disk image from the install file & make a bootable installer using Terminal:

    hdiutil create -o /tmp/Mojave.cdr -size 7000m -layout SPUD -fs HFS+J
  2. Attach that file, with Terminal command:

    hdiutil attach /tmp/Mojave.cdr.dmg -noverify -mountpoint /Volumes/install_build
  3. Build it, with command:

    sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/install_build
  4. Move it to your mac’s Desktop:

    mv /tmp/Mojave.cdr.dmg ~/Desktop/InstallSystem.dmg
  5. Unmount the file:

    hdiutil detach /Volumes/Install\ macOS\ Mojave
  6. Convert it to ISO:

    hdiutil convert ~/Desktop/InstallSystem.dmg -format UDTO -o ~/Desktop/Mojave.iso
  7. Rename it to remove the CDR extension:

    mv ~/Desktop/Mojave.iso.cdr ~/Desktop/Mojave.iso
  8. Exit Terminal via Terminal command:


3. Create a new virtual machine (VM) in VirtualBox:

  1. Download Oracle's VM VirtualBox Manager (https://www.virtualbox.org) & install it on your Mac
  2. Open VirtualBox
  3. Click on New
  4. Select Type: Mac OS X and Version: Mac OS X (64-bit)
  5. Memory size: 8192 MB (at least 3 GB)
  6. Hard disk: Create a virtual hard disk now
  7. Hard disk file type: VDI
  8. Storage on physical hard disk: Fixed size
  9. File location and size: 32.00 GB

4. Tweak the VM before installation:

  1. With your newly created VM selected in VirtualBox, go to SettingsStorage:
    1. Click on Empty → Remove [square with a red cross at the bottom]
    2. Click on Controller: SATA → Add optical drive [CD with a green plus sign] → Add → Find the .iso file you created and click Choose
  2. SettingsDisplay: Video Memory - at least 128 MB
  3. SettingsSystem: Processor(s) - at least 2

5. Install the macOS on your VM:

  1. With your VM selected in VirtualBox, click Start
  2. Wait until the Language selection appears; select your preferred language and continue
  3. macOS Utilities: Disk Utility → Continue
  4. Select VBOX HARDDISK Media → click on Erase in the toolbar
  5. Name the drive as you wish and keep the default selections: Format: Mac OS Extended (Journaled) and Scheme: GUID Partition Map; click Erase
  6. Quit Disk Utility when done
  7. Select Install macOS, Continue, and Agree to the license
  8. Select the hard drive you just erased and Install
  9. MacOS starts installing; wait and be patient! (It took about half an hour for me. The VM may restart at least once in the process.)
  10. Go through the MacOS setup (select your Country, keyboard, etc.)
    • It is recommended that you do not log in with your Apple ID at this time and click Set up later instead
    • I also did not allow Location Services, nor data collection from Apple
    • Once installed, you can eject the installation disc from within the VM
    • It also might be a good idea to go to System Preferences...Software UpdateAdvanced... → uncheck Check for updates

6. Install the latest version of AxoGraph on your VM:

  1. Open Safari within your VM
  2. Go to https://axograph.com/download
  3. Click on Mac OS X 10.4 and up*
  4. Install AxoGraph


Now you can run AxoGraph, as well as other 32-bit applications, on your MacOS Catalina!

  • You should be able to turn off the VM from within, as you usually would shut down your Mac
  • It is booted again by selecting your VM in VirtualBox and clicking Start
  • $\begingroup$ Thanks for the thorough update! $\endgroup$
    – Bryan Krause
    Dec 27, 2019 at 14:00

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.