I have tried everything to get this laptop to boot from an external cd drive to no avail. Windows will recognize the drive but the BIOS won't boot to it. I have the newest BIOS version. I already have secure boot off with the boot setting to CSM. I also have the 1st boot priority set to USB. The external drive successfully boots on my other computers (Both newer and older than the Satellite C855D). Any answers will be much appreciated!