Project configured to spawn Niagara system via Character blueprint in a Code project fails to Cook, then crashes project on open

UE - Niagara - Mar 7, 2019

Project configured to spawn Niagara system via Character blueprint in a Code project fails to Cook, then crashes project on open Discovered when verifying [Link Removed] (also similar to [Link Remo ...

Cross does not respond or crashes when "collide with attached children" is enabled

UE - Simulation - Physics - Apr 13, 2021

Fatal error! Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000000 0x00007ffb09d32bb9 UE4Editor-Engine.dll!USkeletalMeshComponent::CopyClothCollisionsToChildren() [D:\ ...

Cannot package project with landscape to mobile

UE - Platform - Mobile - Aug 4, 2016

Cannot package project with landscape to mobile devices. Packaging fails with the following error: Fatal error! Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x00000002 U ...

Project does not cook with actors containing ModularSynth component

UE - Audio - Sep 11, 2017

A project does not cook with actors containing ModularSynth component. The error is a follows UATHelper: Packaging (Windows (64-bit)): Cook: LogWindows: Error: begin: stack for UAT UATHelper: Pack ...

CLONE - Project does not cook with actors containing ModularSynth component

UE - Audio - Sep 13, 2017

A project does not cook with actors containing ModularSynth component. The error is a follows UATHelper: Packaging (Windows (64-bit)): Cook: LogWindows: Error: begin: stack for UAT UATHelper: Pack ...

Lightmass crashes when lighting is built with material that has "Cast Shadow as Masked"

UE - Graphics Features - Oct 4, 2017

Lightmass is crashing when using a material that has "Cast Shadow as Masked" set to true in its properties. Found in 4.18 P3 CL#3676890 Unable to reproduce in 4.16.3 CL# 3561208 and 4.17.2 CL#365 ...

GeometryCollectionActor SetSimulatePhysics false does not stop Physics Simulation

UE - Simulation - Physics - Nov 28, 2024

If the GeometryCollectionActor (GCA) is simulating physics, calling SetSimulatePhysics(false) does not stop the simulation. If the simulation is paused, calling SetSimulatePhysics(true) does as expe ...

Crash when attempting to change the parent of a material instance constant through editor scripting

UE - Rendering Architecture - Materials - Apr 9, 2025

The built-in class "UMaterialEditingLibrary" provides various editor scripting functions related to creating and editing materials and material instances. One of these functions, UMaterialEditingLib ...

Crash editor when many sequencers are opened continuously

UE - Graphics Features - Dec 3, 2020

Get crashed in editor when opening many sequencers using the EditorUtilityWidget,. It's not in UE4.25.3, but it crashes in UE4.25.4. And it only occurs when NVIDIA Aftermath (r.GPUCrashDebugging=1) ...