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I've tried creating a USB boot drive but it always fails with a message from Syslinux and a boot: prompt.

unknown keyword in configuration file FILE0

I've checked the md5sum of the iso - the iso is fine. This occurs with both the 12.04.2 and 13.04 images. Both the images are the 64 bit variants. I have not tried the 32 bit variants.

None of the computers have Windows 8 installed (Vista / Windows 7).

I've tried multiple tools to write the iso to the usb disk (unetbootin, lili, startup disk creater - but none of them work.

Some posts mentioned to edit the syslinux.cfg file - I couldn't do that as it was a binary file (started with FILE0 and then some binary )

I've also tried multiple USB flash drives and none have worked. The drives work fine otherwise and one of them is brand new. Hence I don't think it is a problem with the USB pen drives either.

I think it's something to do with UEFI - but not sure what. I intend to try the 32 bit versions to check if that is the case as I guess the 32 bit ones are not UEFI?

I'm not sure what's wrong.

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syslinux.cfg must be a text file, not binary, here is the SYSLINUX documentation. Can you just borrow a working file, or create a new one with an entry

label live 
menu label Start Linux 
kernel /casper/vmlinuz 
append noprompt cdrom-detect/try-usb=true persistent file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz --

(remove the persistent file=/cdrom/preseed/ubuntu.seed if you don't have one)

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