15.40 My friend can't join my game in MP.

[molin18]

When my friend tries to connect we get the message: "failed to determine external ip address". I have tried to connect to him aswell.

Describe the problem as best as you can
1. I joined a game and my friend tried to join but we get the "failed to determine external ip address" error.
2. We got the "failed to determine external ip address" error
3. I expected that he join me or i could join him.

I don't have a save file because we have tried to create new maps serveral of times, to if that was the problem its not.
We have been searching for it everywhere.(Youtube,Google and the Factorio Forum.

[Zavian]

Failed to determine external ip address sounds like a NAT issue (NAT is network address translation, which is something routers do, and beyond factorio's control). Static port forwarding should help.
See viewtopic.php?f=49&t=53992 for more info.

Edit: Also see viewtopic.php?f=53&t=50200 for free external hosting, which might be another work around.