My friend can't join my private server

Hello, my friend can’t come on my private serveur, he don’t view it thanks for your help.

You need to add the port you are using (default is 30120) to your modem/router’s firewall to allow outside users to connect to your IP using that port. It clearly says this on the download page for setting up a server.

Port forward the port 30120 (UDP & TCP)

example when connecting as a different user would be xxx.xxx.x.xxx::30120