I recently downloaded the install Yosemite install app from the app store onto my mac hard drive, and all i had available to use was a usb 2 16 gb thumbdrive. I want to use this thumbdrive for something else, and have this install app on a usb 3 thumb drive. how do I copy it over to the new thumb drive? Also, I tried to move the install app from the internal hard drive of my mac to an external hard drive, through both finder and pathfinder, when I tried this but it made my computer hang, and made both finder and pathfinder crash, my external hard drive froze as well. How do I safely remove these installers? without causing my computer to crash or externals to crash?