Multiplayer Not Working – Can’t Host or Join Any Game | Error 4301

[David Chou]

Hi Team and fellow players,

I want to report a serious issue I’ve been experiencing since purchasing Grounded 2.
Right from the beginning, I’ve been completely unable to host my own multiplayer game or join my friend’s server. Every time I try, I get this error:

CreateEndpoint: FailedToQueue: 4301
“There was an error hosting the multiplayer game. Please check your connection and try again.”

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Things I’ve Tried (None Worked):

• Replugging my Ethernet cable

• Restarting PC and router

• Disabling firewall / antivirus

• Logging in and out of Xbox account

• Backing up and deleting local save files

• Enabling UPnP on my router

• Attempting port forwarding for UDP 3074, 3478-3479, 500, 3544, 4500

• Switching between Xbox and Steam versions (if applicable)

Despite trying all of the above, I still cannot join or host any multiplayer session. The issue persists, and I haven’t been able to play the game as intended.

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Request:

Please investigate this issue — either on the server side, or in how save files or NAT connection is handled. A clear official explanation or fix is urgently needed.

Also, if anyone else has experienced this and found a solution, I would really appreciate any advice.

Thanks for your time.