Apple - Error creating bootable USB

The solution may be actually easier than you think!

If you get Error erasing disk error number (-69888, 0) A error occurred erasing the disk. message when trying to create a bootable USB, make sure the USB drive is not currently used by the system or your apps (think open Finder windows or current directory in Terminal).

Erasing Disk: 0%... 10%... Error erasing disk error number (-69888, 0) A error occurred erasing the disk

This error will occur if the usb stick and the main drive have the same name - typically: Untitled

The instructions for creating an OS X usb installation stick typically suggest that the usb stick should be called Untitled. But that would also be the default name of the main drive if it has been reformatted. The solution is to name the usb stick something else and change the command to reflect the new name.

You can check for a name clash in terminal:

cd /Volumes
ls

If there is a Volume called Untitled and another called Untitled 1 then the error is occurring because the command you have issued is trying to erase the main drive and not the usb stick.

Open terminal and use

sudo killall Finder

Shuts down all the weird stuff in the background.

Good luck.