Thank you for your post.
I recommend checking the voltages of the serial port to see if it is supplying the correct voltage to the unit on the correct pins. It should be as follows:
Pin 4 > -7V
Pin 5 Gnd
Pin 7 > +7V
If it is not supplying these voltages then we can either supply you with a
diagram showing how to power the device externally.
If the port is supplying these voltages then I recommend that you check the COM port number assigned to the adapter, you will find this in the device manager.
Michael - Tech Support
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