[MoverExamples] Client crash joining dedicated server, unmodified sample map

General Issues and Bug Reporting (Unreal Engine)
1

Summary

Joining a dedicated server running the unmodified MoverExamples plugin’s L_CharacterMovementBasics map causes an immediate client-side fatal error crash. The dedicated server log shows the client disconnecting with ObjectReplicatorReceivedBunchFail, before the player pawn is spawned/possessed.

What Type of Bug are you experiencing?

Networking

Steps to Reproduce

  1. Create a project with the MoverExamples plugin enabled.
  2. Package a dedicated server build and a client build.
  3. Launch the dedicated server with map L_CharacterMovementBasics.
  4. Launch the client build and connect to the dedicated server.
  5. Observe: client crashes with a fatal error dialog almost immediately after join.

Expected Result

Client joins successfully and can play/move on the dedicated server, same as it does in PIE (Play As Listen Server / multiple PIE clients).

Observed Result

Client crashes with a fatal error window. Server log shows:

[2026.09.08-02.21.00:483][409]LogNet: Client netspeed is 100000
[2026.09.08-02.21.00:494][409]LogNet: Join request: /MoverExamples/Maps/L_CharacterMovementBasics?Name=X-1B842F964786EA90CE4D6FB99C6257C6?SplitscreenCount=1
[2026.09.08-02.21.00:504][409]LogNet: Join succeeded: X-1B84
[2026.09.08-02.21.00:551][411]LogNet: NMT_CloseReason: (Client Disconnect Reasons) 127.0.0.1:59259
[2026.09.08-02.21.00:551][411]LogNet: - ObjectReplicatorReceivedBunchFail
[2026.09.08-02.21.00:552][411]LogNet: UChannel::ReceivedSequencedBunch: Bunch.bClose == true. ChIndex == 0. Calling ConditionalCleanUp.
[2026.09.08-02.21.00:553][411]LogNet: UChannel::CleanUp: ChIndex == 0. Closing connection. [UChannel] ChIndex: 0, Closing: 0 [UNetConnection] RemoteAddr: 127.0.0.1:59259, Name: IpConnection_2147482294, Driver: Name:GameNetDriver Def:GameNetDriver IpNetDriver_2147482424, IsServer: YES, PC: PlayerController_2147482289, Owner: PlayerController_2147482289, UniqueId: Null:X-1B842F964786EA90CE4D6FB99C6257C6
[2026.09.08-02.21.00:555][411]LogNet: UNetConnection::Close: [UNetConnection] RemoteAddr: 127.0.0.1:59259, Name: IpConnection_2147482294, Driver: Name:GameNetDriver Def:GameNetDriver IpNetDriver_2147482424, IsServer: YES, PC: PlayerController_2147482289, Owner: PlayerController_2147482289, UniqueId: Null:X-1B842F964786EA90CE4D6FB99C6257C6, Channels: 18, Time: 2026.09.08-02.21.00
[2026.09.08-02.21.00:556][411]LogNet: UNetConnection::SendCloseReason:
[2026.09.08-02.21.00:557][411]LogNet: - Result=ControlChannelClose, ErrorContext="ControlChannelClose"
[2026.09.08-02.21.00:557][411]LogNet: UChannel::Close: Sending CloseBunch. ChIndex == 0. Name: [UChannel] ChIndex: 0, Closing: 0 [UNetConnection] RemoteAddr: 127.0.0.1:59259, Name: IpConnection_2147482294, Driver: Name:GameNetDriver Def:GameNetDriver IpNetDriver_2147482424, IsServer: YES, PC: PlayerController_2147482289, Owner: PlayerController_2147482289, UniqueId: Null:X-1B842F964786EA90CE4D6FB99C6257C6
[2026.09.08-02.21.00:559][411]LogNet: UNetDriver::RemoveClientConnection - Removed address 127.0.0.1:59259 from MappedClientConnections for: [UNetConnection] RemoteAddr: 127.0.0.1:59259, Name: IpConnection_2147482294, Driver: Name:GameNetDriver Def:GameNetDriver IpNetDriver_2147482424, IsServer: YES, PC: PlayerController_2147482289, Owner: PlayerController_2147482289, UniqueId: Null:X-1B842F964786EA90CE4D6FB99C6257C6

### Affects Versions
5.8

### Platform(s)
Windows

### Additional Notes
Server build configuration: Win64/Development
Client build configuration: Win64/Shipping

Building a dedicated server and client from the UE 5.8.2 engine source code.