Form Extended Structures will only destroy one mesh but not any attached

UE - Simulation - Physics - Destruction - Nov 28, 2014

DESCRIPTION: While using form extended structures enabled for a Destruction mesh one of the meshes will be able to be damaged while any others attached will not fracture or damage at all. For exam ...

Child actor components fail to attach in cooked builds when mobility is set to movable and end up at the origin

UE - Gameplay - Oct 21, 2025

Context: A Child Actor Component allows an actor in Unreal Engine to contain another actor as its child (component). Problem: The problem is inconsistent handling of child actor component mobility ...

[CrashReport] UE4Editor_Engine!FLevelCollection::RemoveLevel() [world.cpp:249]

UE - Gameplay - Dec 1, 2017

This is a common crash that has occurred since at least 4.14 User DescriptionsWas playing in editor and ran around my world composition level a little bit and then hit escape to quit.Using the node ...

[CrashReport] UE4Editor_Landscape!ULandscapeComponent::ReallocateWeightmaps() [landscapeedit.cpp:4208]

UE - LD & Modeling - Terrain - Landscape - Nov 16, 2017

This is an infrequent but longstanding crash that has occurred since at least UE 4.12. User DescriptionsTrying to paint a landscape texture on a seemingly bugged out sector, which was stuck with th ...

"DefaultToSelf" pin ignores parameter type

UE - Gameplay - Blueprint - Mar 5, 2015

A user reported an issue resulting in a crash with callstack pasted below. After a brief investigation I've found that user was able to successfully compile a blueprint where a function taking an ...

[AI] Bad entries in NavigationRepository for Box collision with bCanEverAffectNavigation set to false

UE - Runtime - Character - Oct 26, 2025

Some components continue to dirty the navigation state even if bCanEverAffectNavigation is unchecked. Behavior appears very similar to an existing bug, UE-251496 ([Link Removed]), which involves a ...

Crash rendering image sequence if the Sub-Level with matinee is not loaded

Tools - Apr 15, 2016

Crash rendering image sequence if the Sub-Level containing the matinee is not loaded. This seems to go away if the level is either set to "Always Loaded". Seems to be a result of people not switch ...

[CrashReport] UE4Editor_Persona!FBoneDescription::SetScore() [bonemappinghelper.h:31]

OLD - Anim - Sep 14, 2017

This is a somewhat common crash that appears to occur only in 4.17.1 (possible regression?). Users have not provided any description of their actions when the crash occurs. Source Context 20 ...

Saving Behavior Tree with Blueprint task inheriting from native class invalidates Blackboard key when BP contains a function

UE - AI - Jul 8, 2025

A regression introduced in UE 5.6 causes Blackboard key selectors in Blueprint tasks to become invalid when the Blueprint inherits from a native subclass of UBTTask_MoveTo (or UBTTask_BlackboardBase ...

[CrashReport] Access Violation - UModelComponent::GetPhysicsTriMeshData() [modelcomponent.cpp:673]

UE - Simulation - Physics - Oct 2, 2017

This is a trending crash coming out of the 4.18 Previews. Users have not provided any descriptions of their actions when the crash occurred. The callstack is similar to [Link Removed], which was ju ...