Cant join Listen Server

I start a listen server using the command line parameter: \MyProject.exe Desert?listen -game -port=1337

I tried to connect to the server from a client on the same pc using the console command “open localhost:1337” but it is not working…
What am I doing wrong?

For me localhost won’t work but does. Not sure if it’s related but give it a shot.

Turns out my firewall was blocking the connection even though the instances were on the same pc. Fixed now.
Thanks for your time!