Downgrade El capitan to Yosemite but get halt logo on boot

Hi Generav,

Some 3rd party USB installer creators don't seem to be operating properly for Yosemite and El Capitan, producing the halt symbol you are seeing. Follow these steps and your USB installer will work.

• The drive must be 8GB or more and USB 3 will be quicker.
• If you haven't still got the Yosemite installer then first download it from the Mac App Store in the Purchases section (you may need to hold alt/option while selecting Purchases. Once it's downloaded, just quit the installer and set the downloaded file's name to InstallOSXYosemite.app (make sure only .app, not .app.app)

• Plug in your USB drive into the computer and open Disk Utility (in Applications).
• Select the USB drive from the left sidebar and click on Erase tab.
• Set the name be YosemiteInstaller - leave Format on "Mac OS Extended (Journaled)" and Scheme as "GUID Partition Table"
• Now click on Erase button and wait until the format process completes.
• Launch the Terminalapp (in Applications/Utilities) and copy-paste the following command in, and then hit Enter:

  sudo /Applications/InstallOSXYosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/YosemiteInstaller --applicationpath /Applications/InstallOSXYosemite.app --nointeraction

• This will create the bootable USB flash drive. This takes between 10-20 minutes. Do not interrupt the Terminal or eject the flash drive during the process. Once the process completes, you will see the message "Copy Complete. Done."

The OS X Yosemite bootable USB flash drive will be ready for use and you can start the clean installation process.

Let us know if this gets it working for you 🙂

Max.

Thanks for your swift responce.

Already tried that method and it didn't work for me. Ended up using a third party app.

All this is very new to me as I'm coming from the windows world.

Love learning new things

When you say that the method didn't work for you, what do you mean exactly? Did the Terminal command return some error? Did you allow it to complete until the word "Done." appeared? It says "Complete." before it says "Done." and, if Terminal is quit at that point, the install media can it to be incomplete.

Anyway, the steps I posted have worked for many many people and it's very likely that they'll work for you too if you try them again carefully. The only other thing I can think of is that there is a problem with your USB bus.

for others who get the halt sign, restart and switch usb ports...