Receiver shows the "A second transmitter attempted to connect. Please close it." message repeatedly


The text "A second transmitter attempted to connect.  Please close it." message repeats continuously in the receiver window.


The transmitter.html file is open in more than one application.  This issue is often caused by opening the transmitter file in a web browser for troubleshooting purposes without closing the transmitter dock in OBS first.  Close all open instances of the transmitter, including OBS docks, close and relaunch the receiver, then re-open the transmitter.html in the desired application.