Creating a USB Installer

[groove-agent]

I have a client who decided he would update his OSX Yosemite which bricked his Pro Tools 11 software. I'm trying to downgrade him back to Yosemite by creating a Yosemite USB Installer but I don't think it's as easy as it once was.

You used to easily do this by using "DiskmakerX" or "Install Disk Creator" which are third party utilities. However, I think these worked with the old App Store MacOS installers. Now when you download the installers from the Apple website they're DMG files which contains a PKG file that I believe are simply meant to UPGRADE a previous version of MacOS to a newer version not downgrade like I'm trying to do. If you try using the terminal command suggested by everyone on the internet:

sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Yosemite.app

.. it will always say "command not found". This I think is because the current downloadable versions of MacOS are not "Install OS X Yosemite.app" rather they're InstallMacOSX.pkg files which are not containers with the "createinstallmedia" command in it.

The only way I've been able to create an installer is by finding an older disk installer image on torrent sites and creating an installer DVD.

Has anyone run into this problem before? Did you find a solution?

Thanks in advance.

 

[CoastalOR]

You have to double click the "InstallMacOSX.pkg", which will check to see if the current Mac is capable running the "Install OS X Yosemite.app" and the Mac can support/run Yosemite. If yes to all, then it will create the "Install OS X Yosemite.app" in the Applications folder and launch it. Just Quit the installer app and create the USB installer the way you have in the past.

 

[groove-agent]

Thanks for your reply. What if the Mac has a newer version already installed? Will it not fail?

 

[Fishrrman]

If nothing else you try seems to work, be aware that you can go on ebay.
There are folks there who will sell you a USB flashdrive with the OS installer of your choice pre-installed and ready-to-use.
The cost is around $20 or so.
I've never needed to try this, but again be aware that the option is there.

 

[CoastalOR]

Thanks for your reply. What if the Mac has a newer version already installed? Will it not fail?

It would be more helpful to know specifically what version of macOS you have installed.

Basic/General Rules
Your Mac model must support (be able to install/boot) Yosemite.

Your Mac can be formatted APFS (newer macOS - I tested with Mojave) to create the "Install OS X Yosemite.app" in the Applications folder that can be used to create a USB installer. You can not launch the "Install OS X Yosemite.app" on a boot drive that is formatted APSF. Your Mac must be formatted Mac OS Extended (Journaled) with a GUID Partition Map in order to launch the "Install OS X Yosemite.app".