Using a custom #define as the condition for a UFUNCTION's declaration will cause the function to not show in blueprints

Using a custom #define as the coniditon for an #if / #endif that encapsulates a UFUNCTION that is marked as BlueprintCallable will prevent it from being visible in blueprints despite the #if resolvi ...

"Combine Meshes" Breaks Material Slot Assignment

Tools - Jan 18, 2017

When importing an FBX with several different meshes and multiple materials with "Combine Meshes" enabled the materials will get assigned to incorrect portions of the mesh. I've included a version o ...

[CrashReport] UE4Editor_SlateCore!TArray<FHittestGrid::FCachedWidget,FDefaultAllocator>::Empty() [array.h:1530]

Tools - Nov 10, 2017

This is a trending crash coming out of the 4.18 release. Users have not provided any descriptions of their actions when the crash occurred. Nearly all affected project names reference that this occ ...

If the DataLayerAsset name or asset path changes, Actors registered to it will ignore the DataLayer's settings

UE - World Creation - Worldbuilding Tools - Feb 5, 2023

If you change the DataLayerAsset name or asset path, all Actors registered with that DataLayer will ignore that DataLayer's settings. Specifically, even if you set the DataLayer to the Unloaded stat ...

Bug when trying to Ctrl+Z after Replace Actors

UE - Editor - Workflow Systems - Dec 22, 2023

From the UDN case #00649142: My team noticed a bug where sometimes when using "Undo" (Ctrl+Z usually) the BP they are working on disappears in the level. We were able to find a 100% repro case when ...

MetaSounds isn't working with Modular Game Features - LogMetaSound: Error: Target interface is not registered

Audio-Gameplay-Engineering - Nov 22, 2022

Reproduced 3/3 times. Issue also occurs in //UE5/Release-5.0 - CL 20979098 Binary. Confirmed NOT a Regression. Errors:[2022.11.22-18.11.28:472][  0]LogMetaSound: Error: Target interface is not regi ...

Divergent group barriers in Lumen

UE - Graphics Features - Lumen - Apr 23, 2025

Intel reported GPU crashes on their hardware caused by divergent group barriers in ScreenProbeConvertToIrradianceCS:[numthreads(THREADGROUP_SIZE, THREADGROUP_SIZE, 1)] void ScreenProbeConvertToIrra ...

Editor crashes when setting return value pin to object variable in widget blueprint

UE - Gameplay - Blueprint - Apr 9, 2015

Editor crashes when attempting to set an object variable to a return value within widget blueprints. Frequency: 2/2 Crashreporter: [Link Removed] ...

When use Sequence Camera Shake Pattern, Level Sequence occurs error

UE - Anim - Sequencer - Mar 28, 2022

When I apply the Sequence Camera Shake Pattern to a Sequencer's camera, I get an error when playing it. ...

Opening a DataTable that is set to a Struct that is using a Key variable will crash the editor

Tools - Nov 3, 2015

Opening a DataTable that is set to a Struct that is using a Key variable will crash the editor User Description: I'm getting this crash when using Key variable in DataTable. I was able to repro i ...