Weird bug: struct is not visible in blueprints

[panthernet]

UE5.2.1, VS2022, Win11 x64

Stumbled upon a weird bug where my C++ struct isn’t visible in the Editor. When I compile using Live Code or run debug from VS2022 - it shows! I set up all the BPs and save but upon Editor restart it is not visible again and BPs are failing…

I’ve tried to rebuild VS solution and clean Intermediate folder but it won’t help.

#pragma once

#include "FMobSpawnEntity.h"
#include "FMobSpawnGroup2.generated.h"

USTRUCT(BlueprintType)
struct FMobSpawnGroup2
{
	GENERATED_BODY()

	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "General")
	FString MobGroupId;

	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "General")
	int32 SpawnDelay;

	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "General")
	TArray<FMobSpawnEntity> Mobs;
};

LogLiveCoding: Display: Successfully initialized, removing startup thread
LogProperty: Error: FStructProperty::Serialize Loading: Property 'StructProperty /Game/UtilityActors/MobSpawner.MobSpawner_C:UpdateMobSpawns:Data.Data'. Unknown structure.
LogBlueprint: Warning: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] Could not find a variable named "IsInitialized" in 'MobSpawner_C'.
Make sure 'MobSpawner_C' has been compiled for  Set IsInitialized
LogBlueprint: Warning: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] Could not find a variable named "SpawnData" in 'MobSpawner_C'.
Make sure 'MobSpawner_C' has been compiled for  Set SpawnData
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] Failed to create property Data from  <None>  due to a bad or unknown type (Array of Structures)
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] OnMobSpawn  : unable to determine expected signature - is the delegate pin connected?
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] Could not find an event-dispatcher named "OnMobSpawnEvent" in 'MobSpawnerCpp'.
Make sure 'MobSpawnerCpp' has been compiled for  Bind Event to OnMobSpawnEvent
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] Failed to create property K2Node_CreateDelegate_OutputDelegate from  <None>  due to a bad or unknown type (Delegate)
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] The property associated with  Is Initialized  could not be found in '/Game/UtilityActors/MobSpawner.MobSpawner_C'
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] The property associated with  Spawn Data  could not be found in '/Game/UtilityActors/MobSpawner.MobSpawner_C'
LogK2Compiler: Warning: Source pin 'Data' had null struct object (K2Node_FunctionEntry /Game/UtilityActors/MobSpawner.MobSpawner:UpdateMobSpawns_MERGED.K2Node_FunctionEntry_0)
LogK2Compiler: Warning: Destination pin 'SpawnData' had null struct object (K2Node_VariableSet /Game/UtilityActors/MobSpawner.MobSpawner:UpdateMobSpawns_MERGED.K2Node_VariableSet_2)
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\UtilityActors\MobSpawner.uasset: [Compiler] OnMobSpawn  Signature Error: Unable to determine expected signature - is the delegate pin connected?
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\Maps\TestMap.umap: [Compiler] In use pin  Data  no longer exists on node  Update Mob Spawns . Please refresh node or break links to remove pin.
LogBlueprint: Error: [AssetLog] D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Content\Maps\TestMap.umap: [Compiler] Failed to create property Data from  <None>  due to a bad or unknown type (Array of Structures)
LogAnimationCompression: Display: Fetched compressed animation data for AnimSequence /Game/Characters/Mannequins/Animations/Manny/MM_Fall_Loop.MM_Fall_Loop

Also the weird thing is when I run Live Code it always show that files has been modified when they’re actually not:

File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\StellarProjectEditor\Development\Engine\SharedPCH.Engine.ShadowErrors.h.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\FLevelData2.gen.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\FMobSpawnEntity.gen.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\FMobSpawnGroup2.gen.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\LevelRoutines.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\LevelRoutines.gen.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\MobSpawnerCpp.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\MobSpawnerCpp.gen.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\StellarProject.cpp.obj was modified or is new
File D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Intermediate\Build\Win64\x64\UnrealEditor\Development\StellarProject\StellarProject.init.gen.cpp.obj was modified or is new
Building patch from 10 file(s) for Live coding module D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Binaries\Win64\UnrealEditor-StellarProject.dll
   Creating library D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Binaries\Win64\UnrealEditor-StellarProject.patch_0.lib and object D:\Projects\UE\StellarProject\ProjectContent\StellarProject\Binaries\Win64\UnrealEditor-StellarProject.patch_0.exp
Successfully linked patch (0.000s)

Need help with it as I’m quite depressed and don;t know how to fix it.

[panthernet]

Okay, found the solution myself. It seems that Live Code somehow gone wild and brought some mess with its patches.

To fix this isssue you have to go to ProjectContent\YOUR_PROJECT\Binaries\Win64 folder and delete all the files starting with UnrealEditor-YOUR_PROJECT including patches. Then restart Editor.

Upon restart it will tell you that some files are missing and will rebuild it for you. Now you will have a properly updated and built DLLs for the editor.