UPnP Stack Error

Unable to play A+ to local AVR.
“Error initializing UPnP stack,error; -203 UPNP_ESOCKET_BIND”
How does this happen? And, how to repair ans prevent a reoccurance?.

PS:A+ on Windows 10 Home runs Windows ver fine same network etc.

FOUND it!!!. Had Logitech Media Server running while trying to run A+. Catalina sys prefs and turned off LMS. A+ woks fine. PAIN!!!