Repro Rate: 3/3
This is a live issue where the customer claims that the SteamSockets implementaton is not setup to handle the new Client and Session Id setup that was introduced in 5.1.
This issue was reproduced using a GitHub build of //UE5/Release-5.1 at CL 23058290.
Cannot regression test due to difficulties connecting client to host in //UE5/Release-5.0 at CL 20979098.
[/Script/Engine.GameEngine] !NetDriverDefinitions=ClearArray +NetDriverDefinitions=(DefName="GameNetDriver",DriverClassName="/Script/SteamSockets.SteamSocketsNetDriver",DriverClassNameFallback="/Script/SteamSockets.SteamNetSocketsNetDriver")
: Client can't join the host. The following can be seen in the log:
LogHandshake: Incoming: Rejecting game packet with invalid session id.
: Expected handshake to accept Client and Session ID.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-174140 in the post.