Use Single Process settings adjusted while Use Single Process is disabled are retained while Use Single Process is enabled

UE - Networking - Jul 1, 2015

Use Single Process settings adjusted while Use Single Process is disable are retained while Use Single Process is enabled. This can be problematic when there are issues with having Use Single Proces ...

When Character BP actor is rotated, "Mesh" component translation differs on Client and Server

UE - Gameplay - Apr 21, 2015

Occurs in: Releases 4.7.6 CL:2510309 Main 4.8 CL:2513846 When Character BP actor is rotated, Translation is changed for "Mesh" component on Client. Server appears as expected. This isn't typicall ...

Crash importing FBX

UE - Editor - Content Pipeline - Import and Export - Jan 7, 2015

User reporting as a 4.7 Bug, but no crash report for this bug available for 4.7. Same bug found reported for 4.6.1: Crash Report: [Link Removed] [Code] <unknown module>! KERNELBASE!RaiseExceptio ...

VSCode finds intellisense errors in Project source files: cannot open source file "UBT_COMPILED_PLATFORM/UBT_COMPILED_PLATFORMPlatformCompilerPreSetup.h"

UE - Foundation - Cpp Tools - Jan 28, 2020

VSCode finds intellisense errors in Project source files: cannot open source file "UBT_COMPILED_PLATFORM/UBT_COMPILED_PLATFORMPlatformCompilerPreSetup.h" Similar to [Link Removed], but that was onl ...

FBX Import - Morph target normals not correctly applied when imported as LOD 0

UE - Editor - Content Pipeline - FBX - Nov 27, 2025

This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...

"Primitives with unbuilt interactions" not clearing after lighting scene rebuild

UE - Graphics Features - Oct 29, 2021

Regression No, according to affect version 4.26 and 4.27 [2021.10.29-17.01.06:085][830]Primitives with unbuilt interactions: 6[2021.10.29-17.01.06:085][830] Primitive FoliageInstancedStaticMeshComp ...

In AnimNode_RigidBody.cpp, PhysicsSimulation->CreateActor() is being passed World Space transforms, when it should be getting Local Simulation space transforms

UE - Runtime - Simulation - Jun 24, 2025

In AnimNode_RigidBody.cpp, PhysicsSimulation->CreateActor() is being passed World Space transforms, when it should be getting Local Simulation space transforms. The licensee has reported that FAnimN ...

Drag and Drop fails in Standalone and Packaged builds when WidgetComponent’s Widget is set at runtime

UE - AI Workflows - UI Systems - Dec 4, 2025

When a UWidgetComponent has its widget assigned dynamically at runtime using CreateWidget and SetWidget, drag & drop operations fail in Standalone Game and packaged/game builds, while working correc ...

Server Travel from Map A to Map B then back to Map A will crash on exiting PIE

UE - Gameplay - Jul 10, 2015

Server Travel from Map A to Map B then back to Map A will crash on exiting PIE. Generates different call stacks between 4.8.1 and Main. Crash Reporter: 4.8.1: [Link Removed] Main: [Link Removed] ...

Crash when Live Coding is triggered after engine source edits Blueprints using ChildActorComponent

UE - Framework - Blueprint - Nov 28, 2025

After editing engine source files and triggering Live Coding, derived Blueprints that inherit from a Blueprint containing a ChildActorComponent cause UChildActorComponent::Serialize to run on a Live ...