User Question: I get "Invalid Port Selected". The only option available in the list box is "Autoselect"; no ports are listed even though I have LPT1, 2 and 3 on this machine.STM Response: This is usually a matter of how the port is set up in the BIOS. A small percentage of users must set their parallel port to "Output Only, SPP, Normal," or something similar. Let us know if you continue to have problems after making this change.