Unreal Engine Issues
Unreal Engine Issues
Users project crashes when opening level that loads multiple sub-levels
UE - Foundation - Core - UObject - May 31, 2017Users project crashes when opening level that loads multiple sub-levels. Unable to reproduce this in a clean project so the users project is provided though Epic's box account (link is in the repro ...
TMap does not serialize properly in specific circumstance when it contains a UObject property set to null by default
UE - Foundation - Core - Aug 8, 2018A TMap containing a struct with a UObject reference property (set to nullptr by default) does not serialize properly for an instance where the UObject reference is set on the instance, but the TMap ...
Niagara color picker user parameter preview no longer updates until confirmation
UE - Niagara - Apr 18, 2025Starting with UE 5.4, the Color Picker Tool no longer updates preview values in real time for certain editor windows like Niagara when working with User Parameters. This behavior is a regression fr ...
Compile warning/error in the FUpdateCollisionResponseHelper destructor
UE - Simulation - Physics - Dec 15, 2017It has been reported that when building with Visual Studio 2017 version 15.5.1, a warning/compile error is shown in BodyInstanceCustomization.cpp: warning C4287: '<': unsigned/negative constant mism ...
Noise Material Expression is rendering outside Min and Max Range with High Position Values
UE - Graphics Features - Mar 31, 2015The Noise Material Expression is rendering values well outside the Min and Max Range set in the Expression node. Also Reproduced in Main Promotable-CL-2469752 Alerted the user to suspicions and su ...
VS fails to compile when USTRUCT is referenced as BlueprintReadWrite or BlueprintReadOnly
UE - Foundation - Cpp Tools - UnrealHeaderTool - Aug 22, 2017Defining a FBoneReference variable as BlueprintReadWrite or BlueprintReadOnly in the UPROPERTY macro fails to compile in 4.17. The error message provided by VS states: LogCompile: Error: Type 'FT ...
GAS: GameplayCueNotify OnActive executed twice for Duration GEs on Standalone+ListenServer
UE - Gameplay - Gameplay Ability System - Aug 2, 2023When playing Standalone or as Listen Server, whenever a GameplayEffect with a duration is applied that fires gameplay cues, the server will locally execute OnActive twice on GameplayCueNotify_Actors ...
GenerateProjectFiles.bat fails to compile UnrealBuildTool when VS2019 is the only version of Visual Studio installed
UE - Foundation - Cpp Tools - Apr 1, 2019Attempting to run GenerateProjectFiles.bat on a computer that only has Visual Studio 2019 installed (no other versions of Visual Studio were ever installed previously) will fail to compile UnrealBui ...
Linux: Assertion at splash screen when trying to open UE4Editor
UE - Platform - Linux - Mar 21, 2017I ran into this while looking to verify [Link Removed] at CL 3355923. I logged the issue I was verifying the fix for last night and have not updated anything locally, so the "OpenGL 4.3 not supporte ...
Failed to generate Nanite data for mesh with bDoFastBuild enabled
UE - Graphics Features - Nanite - Oct 1, 2025If "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 ...