Failed to generate Nanite data for mesh with bDoFastBuild enabled

UE - Rendering - 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 ...

Intermittant motion blur issues in content heavy scenes

UE - Rendering - RHI - Jul 30, 2026

When using the following RHI/Render thread/GT sync configuration:r.OneFrameThreadLag 1r.GTSyncType 1 The previous skinning bone data can be corrupted and introduce visual artifacts on everything us ...

User Struct value set through a component is reset to default when modified through the level instance

UE - Gameplay - Jul 3, 2017

Struct value set through a component is reset to default when modified through the level instance. If it's not set through the component, it works fine. User Description: There is a bug in the eng ...

[CrashReport] UE4Editor_Persona!FReferenceSkeleton::FindBoneIndex() [referenceskeleton.h:252]

OLD - Anim - Jul 20, 2017

This is a common crash affecting users in 4.16, and has occurred since at least 4.14, affecting more than 200 unique users. Unfortunately none of them have provided any additional information. Sou ...

[CrashReport] UE4Editor_Landscape!ULandscapeInfo::RecreateLandscapeInfo() [landscape.cpp:2128]

UE - LD & Modeling - Terrain - Landscape - Sep 28, 2017

This is an early trending crash coming out of the 4.17.2 hotfix, with no record of occurring previously. The callstack is very similar to [Link Removed] (fixed in 4.17.2) and may be related. Users ...

Native gameplay tags in plugins are cleared when reading config files

UE - Gameplay - Aug 14, 2024

When references to Gameplay Tags are loaded, it checks to see if they are already registered. If they are not already registered, it will notice it is invalid and may print a warning depending on th ...

Crash Occurs when changing the 'Max Metal Shader Standard To Target' option within iOS Project Settings

UE - Platform - Mobile - Jan 26, 2017

A crash occurs when setting the Max Metal Standard Shader version within the Project Settings for iOS. I tested on both Mac and PC and the crash occurs on both machines. Regression? No, this is not ...

Crash When Attempting to Add Existing Streaming Levels Already Present in the Levels Window

Tools - Aug 10, 2017

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

OnActive Gameplay Cues not activating properly in standalone

UE - Gameplay - Nov 28, 2016

This was reported from https://udn.unrealengine.com/questions/323255/bugfix-onactive-not-triggering-for-gameplaycues-on.html In some case it looks like OnActive gameplay cues are not working proper ...

Second UVs wiped when using Merge Actors Tool

UE - World Creation - Worldbuilding Tools - HLOD - Jan 26, 2017

The merge actor tool no longer saves additional UVs used for the merged mesh. This was not the case in 4.13, but in 4.14 and later this information is no longer present. Also worth noting is that i ...