Unreal Engine Issues
Unreal Engine Issues
Niagara Mesh Renderer registers NumParticles x NumMeshVariants TLAS instances
UE - Rendering - Graphics Features - Ray Tracing - May 28, 2026When using the Niagara Mesh Renderer with multiple mesh variants selected via MeshIndex, the number of TLAS instances allocated is NumParticles × NumMeshVariants and enabling the Path Tracer can ca ...
TMap where key is an FString: initializer list will accept bad MakeTuple
UE - Core - Systems - Sep 2, 2026POST LINK: https://forums.unrealengine.com/t/tmap-where-key-is-an-fstring-initializer-list-will-accept-bad-maketuple/2747443 POST BODY:Summary A TMap where the key is an FString can be created lik ...
Landscape Resize Tool Stall
UE - Graphics Tools - Terrain - Landscape - Oct 3, 2023From licensee: We're trying to reduce component count on our landscape using the resize tool. When modifying the landscape execution never completes. When I hit pause and get a breakpoint to see wh ...
Regression: Several project settings, especially from built-in Plugins, are being silently erased when previously they were not, which is perceived as a bug
UE - Core - Systems - Feb 28, 2025In UE's Project Settings, some pages are saved automatically to the project's "Config/Default<CATEGORY>.ini" file (meant to be version-controlled) on every change. Other pages have buttons "Set as D ...
Editor crash when a spline component is added to a blueprint and compiled
Tools - Sep 7, 2016Most recent user affected CL: 3106830 (4.13.0) Error message: Access violation - code c0000005 (first/second chance not available) Source Context: SelectedKeys = SplineVisualizer->GetSelectedKey ...
[CrashReport] UE4Editor_D3D11RHI!TerminateOnDeviceRemoved() [d3d11util.cpp:176]
UE - Graphics Features - Nov 18, 2016Error message: Fatal error: [Link Removed] [Line: 176] Unreal Engine is exiting due to D3D device being lost. (Error: 0x887A0006 - 'HUNG') Source Context: 161 162 const TCHAR* Rea ...
[CrashReport] UE4Editor_LevelEditor!FLevelEditorActionCallbacks::Paste_CanExecute() [leveleditoractions.cpp:1602]
UE - Gameplay - Blueprint - Jan 17, 2017This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Assertion failed: GEditor->GetSele ...
Hot reload causes placed actor to lose variable references
UE - Foundation - Cpp Tools - Hot Reload - Nov 9, 2017Preforming a hot reload causes placed actors to lose code based variable settings. More repro steps: 1. Open UE4Editor.exe 2. Create a First Person Code project 3. Build the project for Developme ...
5.5 Static Mesh Import Pipeline Regression
UE - Editor - Content Pipeline - Import and Export - Apr 25, 2025This question was created in reference to: [Link Removed] This post references the first post because this problem was not discovered till now. I think it was masked because the issue appears to be ...
Using a Macro to access a variable from another Actor causes a crash in Standalone
UE - Gameplay - Blueprint - Jun 8, 2015Using a Macro to access a variable from another Actor causes a crash in Standalone. This does not seem to affect any other preview in editor, nor packaged games. Reproduced in 4.7.6, 4.8 Preview 4, ...