"Failed to find object 'Class None'" in project log after creation

UE - Foundation - Core - Nov 17, 2014

Users reported seeing the line "LogUObjectGlobals:Warning: Failed to find object 'Class None.'" in the Output log after creating a project. I was able to confirm in a new blank code project without ...

OBJ file causes a `Debug Assertion Failed!` error

UE - Editor - Content Pipeline - Import and Export - Dec 23, 2015

When importing this users file of an OBJ asset there will be an assertion failed error. On the import message if you hit "ignore" until the mesh imports all will work in 4.10 or later. This was no ...

Editor Crashes if GetMaterialIndex is called with an invalid slot name

UE - Graphics Features - Feb 8, 2017

Calling Get Material Index node with an invalid slot name will produce a return value of -1. Passing this value to a Get Material node causes the editor to crash. ...

Steam Sessions fails to create when using the Create Session node

Docs - Nov 30, 2021

This is a Regression. 4.26.2 - Binary - no issue creating a session. 4.27.1 - Binary - no issue creating a session if you convert a previously working 4.26.2 project. 4.27.1 - Binary - Fails to c ...

Missing Triangles on scaled MetaHuman assets with Nanite enabled

UE - Rendering - Features - Nanite - Feb 19, 2025

Additional information: only happens when all three conditions are true: the camera is very close to the character, the MH is Nanite, and a scaled mocap animation is appliedmaterial is opaque, shows ...

MoviePipeline skipped frames using Temporal Subsampling + Time Dilation

UE - Anim - Sequencer - Jun 30, 2020

The frame appears to be getting skipped entirely, but the timing for the frames on either side of them is correct, ie: if frame 10 is skipped, frame 9 and 11 still match the working case, so the ove ...

Landscape raytracing geometry always updates every frame

UE - Rendering - Features - Ray Tracing - Apr 11, 2025

LOD 0 Landscape meshes are always updated in FLandscapeComponentSceneProxy::GetDynamicRayTracingInstances because* r.RayTracing.Geometry.Landscape.LODsUpdateEveryFrame* (GLandscapeRayTracingGeometry ...

Lumen Translucency lighting vs opaque mismatch is larger than expected

UE - Rendering - Features - Lumen - Sep 5, 2025

The licensee's VFX team has been struggling with getting their Niagara systems with translucent materials to fit into the environments they are being used in. In a project with default settings, the ...

Vulkan crashes on Adreno Galaxy S7

UE - Platform - Mobile - Jan 19, 2017

Removing created event from level BP crashes editor if event is tied to object in level

UE - Gameplay - Blueprint - Feb 21, 2015

UPDATE: 2/23/2015 Crash is limited to 4.6.1, does not occur in 4.7 Preview 8 or later builds (CL#2448202). ========================================================== Editor crashes if an event is ...