Testing multicast - not getting proper results

This question was asked before here: https://networkengineering.stackexchange.com/questions/71813/testing-multicast-problem

But I was pointed here.

I use this tool: https://www.winsocketdotnetworkprogramming.com/winsock2programming/winsock2advancedmulticast9a.html

With turned off Windows Firewall and with turned off ESET Security Firewall.

Using:

C:\2>ipconfig
Windows IP Configuration
Ethernet adapter Połączenie lokalne:
   Connection-specific DNS Suffix  . :
   IPv4 Address. . . . . . . . . . . : 192.168.1.103
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 192.168.1.1
Ethernet adapter Ethernet 2:
   Media State . . . . . . . . . . . : Media disconnected
   Connection-specific DNS Suffix  . :

C:\2>mcastws1.exe -b 192.168.1.103 -s
socket handle = 0x000000BC
Binding to 192.168.1.103
Joined group: [224.0.0.255]:25000
Set sending interface to: 0.0.0.0
Set multicast ttl to: 8
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
Sent 1024 bytes to [224.0.0.255]:25000
^C
C:\2>

I get such results:

z:\2>ipconfig
Windows IP Configuration
Ethernet adapter Ethernet:
   Connection-specific DNS Suffix  . :
   IPv4 Address. . . . . . . . . . . : 192.168.1.102
   Subnet Mask . . . . . . . . . . . : 255.255.255.0
   Default Gateway . . . . . . . . . : 192.168.1.1

z:\2>mcastws1.exe -b 192.168.1.102
socket handle = 0x00000100
Binding to [192.168.1.102]:25000
Joined group: [224.0.0.255]:25000
Set sending interface to: 0.0.0.0
Set multicast ttl to: 8
^C
z:\2>

Question: Why I do not get similar results like here: https://www.winsocketdotnetworkprogramming.com/winsock2programming/winsock2advancedmulticast9_files/winsock2multicast009.png

Why I do not get similar results

You first example has -s at the end of the mcastws1.exe command:

mcastws1.exe -b 192.168.1.103 -s

where

-s is Act as server (send data); otherwise receive data

Source: The IPv4 multicast programming tutorial for Windows socket

Try adding the -s flag to your second example.