Many thanks for your suggestion which I have now tried
and variations such as leaving the > off at the beginning
This did not print but it moved a step forward since the open
failed. I also tried putting the : at the beginning
but this was as originally but no file was written to.
Looking at the port for the printer it describes it as a Virtual Printer Port for USB
I do not know if this affects what should be done to make it work
Do you have any more ideas?