Crash: Unhandled exception UE4Editor_Renderer!FMobileBasePassMeshProcessor::Process

UE - Graphics Features - Mar 14, 2019

HUD can cause a crash when used with Mobile. "When running from visual studio exception happens here: https://github.com/EpicGames/UnrealEngine/blob/4.22/Engine/Source/Runtime/Renderer/Private/Mobi ...

TimeSynth when reactivated doesn't continue playback from where it was deactivated

UE - Audio - Dec 9, 2019

This issue only occurs with -audiomixer passed into the Engine (4.23) and in 4.24/4.25 where it is enabled by default. The user tried deactivating and reactivating Time Synth component to pause it ...

Landscape Tool crashes on Layer Import

UE - LD & Modeling - Terrain - Landscape - Mar 12, 2020

The heightmap and weightmaps were created using Terresculptor, and exported in the correct format. If you import everything except the layermaps, the landscape is generated and the layers can be pai ...

Character jumping can become permanently blocked under subpar net conditions

UE - Gameplay - Player Movement - Dec 8, 2023

Problem Under laggy networking conditions, if the user rapidly presses the jump button the character can at some point stop responding to jump input. Initial Thoughts It looks like there's a logi ...

Changing MaterialQualityLevel causes a crash due to a ShaderMap mismatch in UniformExpressionCache

UE - Rendering Architecture - Materials - Nov 26, 2025

A crash may occur when changing the MaterialQualitylevel via Scalability due to a race condition. The issue occurs because in ScalabilityCVarsSinkCallback(), when it creates the FGlobalComponentRec ...

Incorrect number of vertices displayed by ProfileGPU command in Cascade particles

UE - Niagara - Dec 9, 2021

This issue was reported by the licensee, but it's possible that the number of vertices in the particles is higher than it really is. ...

Playing sequences in reverse snaps after sequence has first ran

UE - Anim - Sequencer - Dec 29, 2016

I first came across this bug when I was working with Actor Sequences and noticed that the door I had opening would snap back when I tried to close it. Later I discovered that the issue was with play ...

USkinnedMeshComponent::FindClosestBone does not respect bRequirePhysicsAsset parameter

OLD - Anim - Mar 20, 2017

A licensee has reported that the USkinnedMeshComponent::FindClosestBone function does not respect the bRequiresPhysicsAsset parameter, resulting in the bone returning bones that are not part of the ...

[CrashReport] UArrayProperty::DestroyValueInternal

UE - Gameplay - Blueprint - Sep 14, 2017

This is a somewhat common crash that has affected multiple users in 4.17. User Descriptionstried to compile a blueprint after changing blueprint interface function definitions. Source Code 121 ...

SceneCaptureComponent2D 'Primitive Render Mode' Always Selects Legacy Option

UE - Graphics Features - Nov 9, 2017

When using SceneCapture2D and trying to edit the "Primitive Render Mode" (found in Details panel, Scene Capture) you can select the "Render Scene Primitives (Legacy)" and the "Use ShowOnly List" opt ...