If you are connecting each webcam with USB, make sure your PC recognizes each camera source by checking connection in the computer’s device manager. If the webcam is detected, check your camera source configuration.
Be sure to select “Webcam” as your camera type in the Camera Configuration setup menu. Then, select the camera model you want to use as your camera source in the “IP Address” drop-down field.
If you are using USB extenders to expand your webcams across long distances, please reference the FAQ on USB Extenders.