I get "Couldn't hide boot" in the cleanup phase of UniBeast. The resulting usb does not boot. - I'm using Sierra 10.12.4 in Applications/. - I checked this on a virtual machine with Yosemite (i know i should not ) and on my actual machine using El Capitan. - If i select UEFI Boot Mode the usb is created correctly. - The previous version of UniBeast worked fine in legacy mode, even on the vm (but, as mentioned by others, i was not able to boot 10.12.4 install). - The usb was formatted OS X Extended (Journaled), i checked both GUID and MBR. - I checked 2 sticks (16GB and 32GB). ~/Library/Logs/UniBeast.log 03/31/17 16:34:38 - Starting UniBeast 7.1.0-20170329 03/31/17 16:35:03 - Mounting Volumes... 03/31/17 16:35:04 - Copying Files... 03/31/17 16:45:14 - Detaching Volumes... 03/31/17 16:45:15 - Installing Bootloader... 03/31/17 16:45:51 - Cleaning Up... 03/31/17 16:46:36 - Couldn't hide boot /var/log/install.log (no "Install Failed" entries) I don't think my copy of sierra is corrupted (i'm able to create an install usb from it that run just fine via vmware).