How to reinstall os x yosemite from usb

Posted on 10.06.2018 by Kristeen
Creating a bootable installer disk lets you install Yosemite on multiple Macs and also makes a handy emergency drive. Choose format Mac OS Extended Journaled and name it Yosemite and then click Erase. How to Build a Bootable OS X Yosemite Beta Installer Drive. Before we begin the detailed process of clean installing OS X Yosemite on Macs, there are a few things you'll need to do first.

Creating a bootable Yosemite beta installer uses the same createinstallmedia trick that works with OS X Mavericks bootable installers, with the only differences being in file naming.

When the splash screen launches, quit the installer app DO NOT install Yosemite yet. Reformat your USB drive using Disk Utility. The problem is, I cant find out how to do this without already having a version of OS X already installed on a portion.
Download the OS X Yosemite Beta installer from the App Store you must be a registered participant in the beta program, you can sign up to get it. Once you have everything backed up use the newly created USB drive to do Clean Install of OS X Yosemite. Boot into the USB driver and format the Mac hard drive with Disk Utility. At this stage all of your data with be removed from the Mac hard drive and you can then proceed with the install.