Collision of child actor doesn't rotate if the parent is simulating physics

UE - Simulation - Physics - Aug 11, 2015

Collision of child actor doesn't rotate if the parent is simulating physics. This was an old bug that an AnswerHub user reported back in 4.9 but now a licensee is reporting this same behavior in 4.1 ...

In Editor, Blueprint resources are not freed up when the Blueprint is closed

UE - Framework - Blueprint - Feb 16, 2024

It appears that the preview scene used to render thumbnails is not destroyed after a thumbnail is rendered, even after the blueprint editor is closed and GC is run. Also found in Release-5.4, CL: 31 ...

Internal Compiler error when calling a custom enum in a struct from a blueprint macro

UE - Gameplay - Blueprint - Aug 6, 2015

If a macro is referencing a custom enum within a struct and compiled after another output pin is removed, an internal compiler error will appear and the blueprint will not compile. ...

[CrashReport] UE4Editor_MaterialEditor!CastChecked<UMaterialGraphNode,UEdGraphNode>() [casts.h:192]

UE - Rendering - Architecture - Materials - Aug 31, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

[CrashReport] UE4Editor_Core!FArchive::SerializeCompressed() [archive.cpp:447]

UE - Foundation - Core - Nov 17, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Assertion failed: PackageFileTag.CompressedSize == PACKAGE_FILE_TAG_SWAPPED [L ...

[CrashReport] UE4Editor_Renderer!FBatchingSPDI::DrawMesh() [primitivesceneinfo.cpp:47]

UE - Graphics Features - Jan 3, 2017

Error message: Assertion failed: Mesh.VertexFactory->IsInitialized() [Link Removed] [Line: 45] Source Context: 32 // Keep a reference to the hit proxy from the FPrimitiveSceneInfo, to ensu ...

StructUtils plugin's `FInstancedStruct` in a CPP-defined struct in a `TArray` on an actor component defined in CPP and implemented in BP. Populating the instanced struct in an actor BP's class defaults breaks serialization of the class defaults.

UE - AI - May 30, 2025

Context Instanced structs are great for holding simple data with the main advantage they have is a low memory overhead unlike instanced objects. Problem The problem is in StructUtils plugin's `FIns ...

Animating blueprint mesh duplicates uncontrollably

UE - Gameplay - Components - Apr 15, 2015

When animating within a blueprint of a subclass created in c++, the animating mesh replicates itself uncontrollably. Added to .h: UPROPERTY() UBoxComponent* BoxComp; UPROPERTY() USkeletalMeshCompo ...

Enum Meta is being ignored when project is packaged

Tools - Nov 4, 2014

When using UMeta on Enums, text is ignored when doing Enum to String on a packaged project. ...

Chaos Fields: LS_MasterField continuously creates components every frame and never cleans them up

UE - Runtime - Deformable - Mar 25, 2026

While active and ticking, the built-in FS_MasterField actor instance continuously creates several new components every frame, which are never cleaned up until the actor is destroyed. This can happen ...