Unreal 5.4 problem with a packaged game! Server spawns the character and client disconnecting with ‘Failed to load package’ error.

[WellingOne]

LogNetPackageMap: Warning: GetObjectFromNetGUID: Network checksum mismatch. FullNetGUIDPath: [33]/Game/VGame/Character/BP_MainPawn.[31]Default__BP_MainPawn_C, 1670283495, 1022904269
LogNetPackageMap: Warning: InternalLoadObject: Unable to resolve object from path. Path: Default__BP_MainPawn_C, Outer: /Game/VGame/Character/BP_MainPawn, NetGUID: 31
LogNetPackageMap: Warning: InternalLoadObject: Unable to resolve object. FullNetGUIDPath: [33]/Game/VGame/Character/BP_MainPawn.[31]Default__BP_MainPawn_C
LogNetPackageMap: Error: UPackageMapClient::SerializeNewActor. Unresolved Archetype GUID. Path: Default__BP_MainPawn_C, NetGUID: 31.
LogNetPackageMap: Error: UPackageMapClient::SerializeNewActor Unable to read Archetype for NetGUID 10 / 31
LogNet: Warning: UActorChannel::ProcessBunch: SerializeNewActor failed to find/spawn actor. Actor: None, Channel: 6
LogNet: Error: UEngine::BroadcastNetworkFailure: FailureType = NetChecksumMismatch, ErrorString = GetObjectFromNetGUID: Network checksum mismatch. FullNetGUIDPath: [33]/Game/VGame/Character/BP_MainPawn.[31]Default__BP_MainPawn_C, 1670283495, 1022904269, Driver = Name:GameNetDriver Def:GameNetDriver IpNetDriver_0
LogNet: Warning: Network Failure: GameNetDriver[NetChecksumMismatch]: GetObjectFromNetGUID: Network checksum mismatch. FullNetGUIDPath: [33]/Game/VGame/Character/BP_MainPawn.[31]Default__BP_MainPawn_C, 1670283495, 1022904269
LogNet: NetworkFailure: NetChecksumMismatch, Error: ‘GetObjectFromNetGUID: Network checksum mismatch. FullNetGUIDPath: [33]/Game/VGame/Character/BP_MainPawn.[31]Default__BP_MainPawn_C, 1670283495, 1022904269’

I comment that code ,but not work for me. Sad …

@NV_gnoowik

You need to fix engine codes:

• In Character.h, FRepRootMotionMontage struct.
• In GameplayAbilityRepAnimMontage.h, FGameplayAbilityRepAnimMontage struct.

Try to mark NotReplicated on UPROPERTY or delete variable AnimMontage_DEPRECATED

In Character.h

#if WITH_EDITORONLY_DATA
    /** AnimMontage providing Root Motion */
    UPROPERTY(NotReplicated, meta = (DeprecatedProperty, DeprecationMessage = "Use the GetAnimMontage function instead"))
    TObjectPtr<UAnimMontage> AnimMontage_DEPRECATED = nullptr;
#endif

In GameplayAbilityRepAnimMontage.h,

#if WITH_EDITORONLY_DATA
	/** AnimMontage ref */
	UPROPERTY(NotReplicated, meta = (DeprecatedProperty, DeprecationMessage = "Use the GetAnimMontage function instead"))
	TObjectPtr<UAnimMontage> AnimMontage_DEPRECATED;
#endif