"Join Session" Always fails even over LAN. Session definitely exists and is easily found but can't be joined

Development Programming & Scripting Multiplayer & Networking
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2

I would suggest that you:

  1. ensure that only the NetDriverDefinitions are in you’re config only 1 time. I had found a ‘copy’ of the line added under

[/Script/Engine.Engine]

was overwriting it.

Thus check:
/Script/Engine.GameEngine

has the Steam netdriver defined and net defs for “/Script/Engine.Engine” are removed

  1. I’m using the SteamSockets plugin, but it works out to be the same, but here is how I had to do my net defs to get it to work (note the fallback driver is still Steam):

Snippet

+NetDriverDefinitions=(DefName=“GameNetDriver”,DriverClassName="/Script/SteamSockets.SteamSocketsNetDriver",DriverClassNameFallback="/Script/SteamSockets.SteamNetSocketsNetDriver")

Hopefully either this fixes it or can at least help you rule it out.