Bind outgoing socket connection to specific interface doesn't always work on Windows 11

[moriartyEZ]

For a VPN app on a Windows 11 machine I have my regular wifi interface (192.168.3.7) and a Wintun Tunnel interface (configured to have IP 192.168.3.6). The routing tables are set up so that all traffic should go to the Wintun Tunnel by default. However the app still needs to be able to make some connections using the wifi interface. I tried creating a socket and binding it to that interface's IP. On one of my Windows 11 machines that works as expected and the socket's traffic is routed to wifi. But on another machine the traffic is still routed to Wintun. Why doesn't this setup work correctly

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