Ubuntu – SYSLINUX: No DEFAULT or UI configuration directive found!

bootlive-usbusb

I have a USB live key created with Linux Live USB creator. I used all the defaults, and got a standard version of Ubuntu. When I try to boot into it, I get the error above. I went through the rest of the threads with no avail.

Things I tried:

  • Renaming the files (my files were already syslinux.cfg, etc.)
  • Typing in mboot.c32 -c boot.cfg into the boot:__ prompt

Any help would be appreciated!

Best Answer

General answer

Generally the iso image that are intended to be burned and booted from CD/DVD has all the files required for boot in the isolinux folder. Whereas the iso images that are intended to be run from USB has all the files required for boot in the syslinux folder. So when you try to burn and boot a CD/DVD iso from USB, it cannot recognize the type of boot medium as it will not have syslinux folder it will simply give Boot failure : No DEFAULT or UI configuration directive found!.

General solution for the Error

Open the USB installation media, then rename the following:

isolinux –> syslinux (folder)
isolinux.bin –> syslinux.bin
isolinux.cfg –> syslinux.cfg

The system looks for these two files (.bin & .cfg) in the syslinux folder at root of the device. So make sure you have both files in the syslinux folder.

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