Build All Levels fails with duplicate level instances

UE - World Creation - Worldbuilding Tools - Level Instances - Jan 24, 2024

Adding "Add Velocity" module to event handler stage causes ensure (ensureMsg)

UE - Niagara - Scripting - Dec 19, 2023

Adding a module which has Required Dependencies (such as "Add Velocity") to event handler stage causes ensureMsg. > > In system /Game/NewNiagaraSystem.NewNiagaraSystem, module AddVelocity (NiagaraN ...

The Starter Contents SM_Statue exists in a bad state, leading to crashes when trying to open levels where it is referenced

UE - Graphics Features - Ray Tracing - Feb 18, 2025

The SM_Statue exists in a bad state leading to a crash when it is loaded or anything that references it is loaded, e.g. Minimal Default level in the Starter Content. It can be deleted as a temporar ...

iPadOS AR App Crashes when ARKit's "Use Scene Depth for Occlusion" is Enabled

UE - Platform - XR - Dec 13, 2024

Does not crash in 5.4 on same hardware so looks like a regression. Attached Unreal logs indicate source of critical error: 'FARKitCameraOverlayMobilePS' shader uniform expression set mismatched sh ...

Distributed HLOD builds always fail for projects not under the Engine Root

UE - World Creation - Worldbuilding Tools - HLOD - Dec 4, 2024

In BuildProject.txt, to make relative path to the project outside the engine root, all paths contains “..” after action command directory. D:/dev/UnrealEngine-5.5.0//HLODTemp/f09bf0f5/HLODBuilder0 ...

WP HLOD Crash on Small Cell Sizes

UE - World Creation - Worldbuilding Tools - HLOD - Jan 8, 2024

Editor crash while saving asset during cook operation

UE - Foundation - Data Pipeline - Cooker - Apr 2, 2025

It is possible to experience an editor crash in 5.5.4 when the cook process generates a warning that references an asset while the editor is saving. It seems that during a save operation, the code t ...

Crash when splitting a UDS pin on a collapsed graph

UE - Gameplay - Blueprint - Jan 27, 2017

I came across this bug while attempting to verify UE-41073. That bug is verified, but I accidentally added the struct into the collapsed node without going into the collapsed graph and split the col ...

Crash When Opening a DataTable Based Off a Struct With a Timecode Variable

UE - Anim - Sequencer - Mar 30, 2020

When a datatable is based off a struct with a timecode variable it will crash when opening. Found in 4.24.3 CL#11590370 Reproduced in 4.23.1 CL#9631420, 4.25 Preview 4 CL#12366721, 4.26 CL#12123513 ...

Spawnable Level Instance via Sequencer in WP map

UE - World Creation - Worldbuilding Tools - Level Instances - Aug 21, 2023

ULevelInstanceSubsystem::OnActorDeleted: check(!IsEditingLevelInstanceDirty(LevelInstance) && !HasDirtyChildrenLevelInstances(LevelInstance)); ...