Android ETC2 Debug Builds Crash on Startup

UE - Platform - Mobile - Sep 9, 2020

Android apps build with the debug configuration on ETC2 will crash on launch. ...

Crash when using Ctrl+Z to undo a single digit change in the size of a widget

UE - Anim - Sequencer - Feb 21, 2017

When trying to undo a single digit change the editor will crash. For example, if a user highlights and replaces a single number in the size of a widget and then attempts to undo, the editor will cra ...

Lighting channels not working as expected when enabling Ray Tracing Shadow

UE - Graphics Features - Lumen - Oct 13, 2020

Non-Ray Tracing Shadows are only cast from lights on meshes assigned to the same Lighting Channel. When enabling Ray Tracing Shadows this is not the case. Lights will still cast Ray Tracing Shadows ...

Crash when calling SetState inside state machine OnUpdate

UE - Anim - Sep 5, 2025

The crash happens when SetState is called inside the function bound to OutputAnimationPose’s OnUpdate in the animation state. This way of using Set State node is the same as shown in the official do ...

Crash, Couldn t find Shader FHitProxyVS for Material Resource M_Glass

UE - Graphics Features - Aug 18, 2014

Changing the properties of M_Glass and M_Metal_Copper to two sided via the property matrix crashes the editor to desktop. (Note: M_Glass with ANY of the M_Metal Materials except M_Metal_Chrome will ...

Crash when using StaticDuplicateObject with mismathced Source and Destination class types

UE - Foundation - Jun 19, 2025

Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...

Editor crash when adding mesh renderer elements in Niagara

UE - Niagara - Jul 8, 2025

When adding multiple meshes to a Niagara Mesh Renderer Module, a check() will be triggered due to a mismatch in the number of Widgets and the number of Tooltip Widgets. ...

Crash when Undo after deleting a Material Layer of a Material Instance.

UE - Rendering Architecture - Materials - Apr 2, 2025

In Unreal Engine version 5.5.4, the Editor crashes when performing Undo after deleting a Material Layer of a Material Instance ...

Add Submix Effect Blueprint Does Not Have Any Effect

UE - Audio - Dec 11, 2020

Adding a second effect to the Submix Effect Chain on a Submix works as expected, but when trying to add a Submix Effect via Blueprint, there is no effect.  This also applies to "Add Master Submix Ef ...

GAS: Removing an AttributeSet followed by removing an active GameplayEffect results in client crash

UE - Gameplay - Gameplay Ability System - Aug 23, 2023

Gameplay Ability System Standalone: Removing an attribute set and then removing an active gameplay effect that has a modifier for an attribute from that set results in a crash. Currently, one must ...