Error message..Another process seems to be outputting to lights.........

[GALENM]

I am just starting/learning to control lights using an arduino as a controller. I am running Windows 7 on a laptop.

When I start xlights 2017.32 and create a sequence then click the lightbulb, the error message above appears. this message only appears on first startup.
The result is that I cannot control the lights. At the controller it has run the test pattern and gone solid red and my commands from xlights do not affect the lights?
It would appear that there is another program/process running in the background that is interfering with my signal to the controller.

[Agingbeaver]

I have not been able to get a USB Dongle that runs fine under Vixen 3, to work with Xlights when running with a Falcon 16v3.
The warning message comes up "Another Process....is outputting" and x Lights literally freezes.  I have to force quit.   My system is Lubuntu 18.04.    If I deactivate the USB and just have E1.31 running, things are ok..

I had to move my DMX network over to a serial output off of the Falcon.