Sleekbook 15-b003ee not booting from CD or USB !

Hi guys .. I have an old HP Sleekbook which I'm trying to run some diagnostics tests on at boot time, however I'm having trouble trying to get the laptop to boot from an external CD drive, or from a bootable USB. I've tried both on all 3 USB ports, but the laptop still just boots from the internal hard drive. I've gone into the BIOS and have set CD and external USB/HDD options are higher priorities but still it doesn't work. I have also enabled Legacy mode in BIOS and have set the same boot...

Sleekbook 15-b003ee not booting from CD or USB !

Sleekbook 15-b003ee not booting from CD or USB !