UE4 Connecting to listen server fails because map could not be loaded

Hi forum,

me and a friend are making a rts game and we are having problems implementing the multiplayer:

We want to listen and join via ip but as soon as we do that UE4 gives us the follwing error:


Failed to load package: /Game/Maps/UE_PIE_Map1

The listener uses “open Map1?listen” and the client uses “open 127.0.0.1” while the game is running. The map “Map1” exists on both sides. Both sides are instances of the same uproject.

One more thing I am curious is on which ip adress the listener is starting? Is it the ip of the first internet adapter? Can I change that ip? Is it a * wildcard and all ips would work?

I really hope you can help us since we are stuck at this for 2 weeks now.

Hey this can be becuse the content needs to be cooked.
I recomend you add the Map in the Packaging Settings to ensure that the Map is packaged.
Also under Edit > Project Settings > Maps and Modes.
You can set the default map for editor, client and server to start the map automaticly.

The listening server will have the same IP as the host its on.
All machines have this IP 127.0.0.1 (it is called the loopback address) and will loop back to the same machine.
So if you are testing with two machines and they are on the same network, then you will need the local IP for the listening server.

On Windows you can get this by Start > Run > CMD (and type ipconfig or ipconfig /all for all adapters).
If you are connecting over the internet you need the public IP can be found e.g: .
You will in most cases have to open some ports for someone to connect as well.

Ty, we cooked it and still the same error ):