Did you boot from CD using the alt-key boot menu?
i hadnt tried that ive put the cd drive back to jae5 connector and booted 1 of my many copies of morphos 3 holding the alt key and selecting the cd and its installing as i type this. the bit i dont really understand is it was booting from my 2.7 disk fine from usb but any way all working many thanks for your help jacadcaps.
very strange just rebooted morphos with disk still in and this time it booted from cd with out me doing anything oh well its working. many thanks for your help.