GameplayTagContainers can cause a crash in packaged builds when Event Driven Loading is enabled

UE - Gameplay - Dec 15, 2017

A user has reported that using a GameplayTagContainer can cause a packaged build to crash when EDL is enabled in certain cases. In this case, if the base C++ class that includes this GameplayTagCont ...

RigVMRegistry : The registry is not locked for writing yet : ensure statement error during cook

UE - Anim - Rigging - Control Rig - Sep 2, 2025

I am seeing an cook failure at the very beginning. It goes away with a retry step via Horde. Please find attached call stack. I am able to consistently reproduce it by wiping all the DDC cache and ...

Crash after Disabling Post Process Blueprint on a Skeletal Mesh

OLD - Anim - Aug 20, 2019

Changing the Anim Class in the Details Panel before Disable Post Process Blueprint can prevent the crash from occurring. Changing the Animation Mode does not seem to prevent this crash.  The conten ...

Adding a code class to a blueprint project causes the editor to crash

UE - Foundation - Core - Oct 5, 2017

Adding a code class to a blueprint project causes the editor to crash after attempting to hot reload. This only occurs for a fully bluprint project, code projects or BP projects that have already h ...

Editor crash when attempting to access Window menu bar after compiling plugin through the editor

UE - Foundation - Cpp Tools - Plugin System - Jan 27, 2016

The editor will crash if the Window menu button next to Edit is pressed after compiling a toolbar plugin through the editor and attempting to click/use it. ...

Blueprint interface function with the same name as a node gets fused

UE - Gameplay - Blueprint - Nov 29, 2017

Creating a Blueprint interface and changing its function name causes a crash when using the undo button to change the name back. ...

[Interchange] Ensure when re-importing an asset that was import with a blueprint pipeline

UE - Editor - Content Pipeline - Import and Export - Mar 14, 2025

The issue is in UInterchangeAssetImportData::ProcessPipelinesCache() The following iteration do not find blueprint pipeline, not sure about python pipeline, it need to be test. TMap<FString, UClas ...

Intermittent Crash in SGraphNode when saving

UE - Gameplay - Blueprint Editor - Apr 5, 2016

Licensee observed crash in SGraphNode after modifying comments on blueprint nodes and saving. Has seen similar crashes before, unable to figure out how to reproduce them. ...

Parameter distributions can be reset to None in Cascade Particle Systems, causing Cascade to Niagara conversion to crash the editor.

UE - Niagara - Apr 18, 2022

Cascade to Niagara conversion causes the editor to crash due to any distribution parameter in the Particle Emitter being reset to none. Repro Rate: 4/4 Tested this in //UE4/Release-4.27 @ CL# 1831 ...

Crash When Substance Material Is Applied to a Mesh In HLOD System

UE - World Creation - Worldbuilding Tools - HLOD - Sep 3, 2018

Crash when Substance material is applied to a mesh included in the HLOD system. Working as expected in 4.19 CL# 4033788. Unable to test issue in 4.21 CL# 4339215 due to plugin dependency. Found in ...