Actors unrelated to the changelist being validated cause errors

UE - World Creation - Worldbuilding Tools - World Partition - Nov 22, 2023

When validating a changelist, unrelated errors to the changelist can appear. Here's an example of running the validation on a cl named "temp cl" which just contains a single actor "Cylinder". The A ...

Failed to generate Nanite data for mesh with bDoFastBuild enabled

UE - Graphics Features - Nanite - Oct 1, 2025

If "bDoFastBuild" is enabled on a Static Mesh asset, in-editor it will never be able to have Nanite data built for it, preventing the Static Mesh from using Nanite. There is no way to fix this issu ...

The Random Audio Node Function 'Randomize Without Replacement' does not Function Correctly

UE - Audio - Apr 6, 2015

When attempting to play random sounds using the 'Random' node within the audio editor, the 'Randomize Without Replacement' does not function as explained via the tooltip. The options says that if y ...

Project Crashes on Open when Implementing An Interface and Its Duplicate

UE - Gameplay - Blueprint - Apr 25, 2016

The linked project crashes on open after attempting to implement an interface and a duplicate of that same interface with different function names. This has not been reproduced in a clean project, h ...

Light as If Static setting does not Persist when Re-opening Project

Tools - Apr 28, 2016

This bug was originally entered back in 4.8 as [Link Removed], but was closed as by design. The reason was, the mesh did not have Lightmap UVs, so using the 'Light as If Static' option would not wor ...

Potential Memory Leak when frequently terminating and re-initializing FConstraintInstance

UE - Simulation - Physics - Mar 29, 2022

From User: When frequently terminating and re-initializing the FConstraintInstance, there appears to be a leak when cleaning up the disabled joint, which leads to an ever growing list that gets sort ...

Custom Primitive Data on BP instance not taking affect while in editor

UE - Rendering Architecture - Apr 5, 2023

Original Repo is from 4.27, however, it still happens in 5.2. This is happening because the Instance Data system does not update the field UPrimitiveComponent::CustomPrimitiveDataInternal from the d ...

Level Object value is lost when a new level is loaded using the same BP

UE - Gameplay - Blueprint - Dec 2, 2021

First discovered this on Linux in //UE5/Main. In the repro, you play from level 2; if you opened Level 1 and played from there, the same outcome would occur. LogNet: Warning: Travel Failure: [Clien ...

Assets with Render in Main Pass disabled show shadow artifacts

UE - Graphics Features - Apr 18, 2016

This issue was originally reported specifically for Destructibles, but it appears to affect Skeletal Meshes, and static meshes when selected. When "Render in Main Pass" has been disabled skeletal an ...

[CrashReport] UE4Editor_Renderer!FUniformMeshConverter::Convert()

UE - Graphics Features - Aug 3, 2017

This is a regular crash that has occurred through 4.16 and into the 4.17 previews. The callstack is similar to [Link Removed] (invalid), although the error message is different. User Description ...