Using the BuildGraph to create an installed binary build of the Engine will fail if Simplygon is not installed.

UE - Foundation - Horde - BuildGraph - Oct 13, 2016

A user reported that attempting to create an installed binary build of the Engine using BuildGraph will fail. This seems to be because we include the UE Simplygon implementation, but do not disable ...

Plugin dependencies causing RI parameter initialization failures (UDN)

UE - Niagara - Oct 6, 2023

Error on some Niagara emitters using the WindForce module: LogNiagaraEditor: Error: Invalid input type found while attempting initialize new rapid iteration parameters. Function Node: /Game/FX/Expl ...

Destructible Meshes that are fractured while using moving will rest and then move the whole components fractures as a whole

UE - Simulation - Physics - Destruction - Nov 26, 2014

DESCRIPTION: When a destruction mesh has been setup to move to a location or use a lerp if it is destroyed the components will fall, come to a rest, and then the entire destruction destruction mesh ...

Crash with FBX with LODs when distance fields and Generated Lightmaps are enabled

UE - Graphics Features - Jan 12, 2015

DESCRIPTION: When importing a mesh with 1 or more additional LODs when Generate Mesh Distance Fields has been enabled via the Project settings will cause a crash if the import options include using ...

Mutable: Child parameters hidden when intermediate Object Group uses "All Options"

UE - Anim - Mutable - Mar 31, 2026

FCustomizableInstanceDetails::FillChildrenMap() unconditionally registers parent-child relationships via __ParentParamName metadata without verifying the parent exists in the active parameter list. ...

World Partition Editor minimap build failed

UE - World Creation - Worldbuilding Tools - Aug 10, 2023

The issue was reproduced when building a minimap for an open world level with no Actors with "Is Spatially Loaded" enabled. Placing additional Actors with "Is Spatially Loaded" enabled in the level ...

GameplayTagQuery AutoDescription not refreshed after GameplayTag redirect on load

UE - Gameplay - Gameplay Tags - Jan 21, 2026

FGameplayTagQuery does not refresh its cached AutoDescription after GameplayTag redirects are applied during asset load. As a result, after renaming a GameplayTag and restarting the editor, the Game ...

SplineMeshComponent's collision will start to distort the longer the Spline becomes

UE - Gameplay - Nov 30, 2016

SplineMeshComponent's collision will start to distort the longer the Spline becomes This is a regession. It was working in 4.13.2-3172292 User Description: When drawing out a long spline mesh ( r ...

Sphere Reflection Captures overridden by Skylight

UE - Rendering - Graphics Features - Jun 10, 2025

When using non-Lumen lighting and Screenspace reflections off, the skylight location overrides the Reflection Capture location during Build Reflections. This results in a Reflection Capture taken fr ...

Crash when recombining Value Pin after swapping Target Wild Card pin from a Vector2D to a Vector on a Set By-Ref Var node

UE - Gameplay - Blueprint - Jul 18, 2022

This is not a regression. Tested in //UE4/Release-4.27 CL18319896 Crash when recombining Value Pin after swapping Target Wild Card pin from a Vector2D to a Vector on a Set By-Ref Var node.  ...