It seems that the port you have chosen can't be used. To fix this, there are several things that you can do. Check the settings of the used LPT Port. If it's set to "bi-directional, EPC or EPP" mode, try changing this to "standard mode". After you did this, try again. If the error message is still appearing, try going to Options > Generator Interface and instead of LPT1 choose LPT2. This might help. If you still have problems regarding this application, you can check the Help menu for additional information.