With COM1 my LabVIEW 5.0 program works fine. When I switch to COM3 (USB to serial converter) only write operations work. The FTDI Win2k driver should work with every application based on the Win32 COMM API. So does LabVIEW use the Win32 COMM API for serial communication under Win9x,NT,2k or does it provides its own driver?
I am also having the same problem with the same setup, but have found if you go into a terminal program first and get it to init. the serial port, when you come back to labview you can read and write to the port. I would think then that labview is not initializing the port thourgh the usb to serial driver. What do you think?