I created USB live for two different distributions on a Lenovo X230T running the latest 15.04 (this bug still exists after four years?!) and when booting both on this machine and on another, I get the syslinux "unknown keyword in configuration file" error and a "boot" prompt. After a few seconds, it hangs.
The workaround is to (quickly) type "help" and press enter twice.
I created USB live for two different distributions on a Lenovo X230T running the latest 15.04 (this bug still exists after four years?!) and when booting both on this machine and on another, I get the syslinux "unknown keyword in configuration file" error and a "boot" prompt. After a few seconds, it hangs.
The workaround is to (quickly) type "help" and press enter twice.