Reply to something went wrong with creating the memory image

so after entering this command


dfu-programmer at90usb162 flash --debug 1 midifighter.hex


where midifighter.hex is replaced with midifightercc.hex

which is the firmware i want to install and is also located on my desktop, I get the message error opening file
and
something went wrong with creating the memory image

What am I doing wrong, i can't work it out.

have got xcode and and all that and have followed instructions to the letter

all the best

tom