Hi,

I created an UDP Multicast Server sketch, and that works OK. The sketch accepts UDP packets sent to the Multicast IP address, and sends a confirmation packet back to the UDP Client.
(ref. http://www.esp8266.com/viewtopic.php?f=29&t=2464 ).

Now I would like to create a sketch where the ESP is a client sending packets to an Multicast UDP server, but I am having difficulty understanding the exact use of the functions in WiFiUdp.h.

This code compiles and runs, but packets are not received by the Server. I checked the server, it receives UDP Multicast from another client perfectly.

Also tried this with the same result:

So I am confused now, give us a hint!