FIXIF: Using the Merge Blueprints feature crashes the editor

UE - Gameplay - Blueprint - Feb 18, 2015

Using the Merge Blueprints feature crashes the editor. This repro is for clicking between the error and warnings while merging, but the editor will generally crash if the Merge is finished or if an ...

Blueprints break when implementing a duplicated BP interface along with the original

UE - Framework - Blueprint - Mar 1, 2024

When duplicating a blueprint interface, the GraphGuids of the original BP interface's function graphs are unchanged: function graphs across the two BP interfaces now have the same GraphGuid. This is ...

When importing an FBX with Combine Meshes = False, one uasset will be created for the collection of assets.

Tools - Feb 4, 2016

When importing a mesh, there is an option to Combine Meshes, which by default is checked. Unchecking this option will bring in the individually named parts contained in the FBX as unique objects in ...

Users Unable to create C++ Projects

UE - Foundation - Core - Mar 6, 2015

2nd AH post with the same issue: https://answers.unrealengine.com/questions/183441/cant-load-c-projects.html Multiple people have reported not being able to create a C++ project. Creating a Bluepr ...

Lightmass: Blocky lightmap artifacts appears on the Mesh Actor which is shadowing by a single face mesh

UE - Graphics Features - Lumen - Jun 9, 2020

Begin Map Begin Level Begin Actor Class=/Script/Engine.StaticMeshActor Name=Plane_2 Archetype=/Script/Engine.StaticMeshActor'/Script/Engine.Default__StaticMeshActor' Begin Object Class=/Script/En ...

[CrashReport] UE4Editor_Engine!LoadSpecialMaterial() [unrealengine.cpp:1523]

UE - Graphics Features - Nov 10, 2017

This is a longstanding crash that has occurred for more than 200 users since at least 4.13. Based on user descriptions this appears to permanently corrupt a project. User DescriptionsI just turned ...

The Geometry Collection Dataflow node CreateGeometryCollectionFromSources is breaking Material Assignment

UE - Simulation - Visual - Jul 21, 2025

The Geometry Collection Dataflow node CreateGeometryCollectionFromSources is breaking Material Assignment. As the licensee has pointed out, this previously worked in 5.5. The most probably cause fo ...

[CrashReport] UE4Editor_CoreUObject!UObjectPropertyBase::Identical() [propertybaseobject.cpp:60]

UE - Foundation - Cpp Tools - Hot Reload - Nov 17, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Access violation - code c0000005 (first/second chance not available) Source C ...

User-defined InstancedStaticMeshComponent subclass misbehave in SCS Editor

UE - Framework - Blueprint Editor - Oct 13, 2025

Context Users can create InstancedStaticMeshComponent (ISMC) (blueprint) subclasses. Any ISMC class can be added to an actor blueprint. When a mesh is selected and transforms are added to the Insta ...

Crash when a subsystem calls GetSubsystemArray() on its owner while engine code is iterating on subsystems also obtained through GetSubsystemArray()

UE - Gameplay - Aug 6, 2024

In some occasions, engine code iterates over a certain subsystem type by calling FSubsystemCollection::GetSubsystemArray() and then calling some method on all subsystems of the returned array. This ...