LAN Error

[MisterRobota]

Hello
I'd been playing LAN on the CnCNET client just fine for the past few weeks but just today I started getting this error
I tried reinstalling, re-updating and nothing works! It was working just fine and now it's not.
Any clue or help is much appreciated!
Oh also, online works just fine. Only LAN has this issue
The error is :
KABOOM

A socket operation was attempted to an unreachable host

I was told on the Discord server that it is " something else using the port maybe? " but I couldn't find anything. It is possible I didn't have enough networking experience to figure it out on my own and that's why I'm very desperate for anyone to help