Unreal Engine Issues
Unreal Engine Issues
Preview Rendering Levels Do Not Display Supported Optimization Viewmodes in Viewport Dropdown
UE - Platform - Mobile - Apr 2, 2019When attempting to set an optimization viewmode while using a Preview Rendering Level other than Shader Model 5, the Optimization Viewmodes dropdown is missing all of its options and instead display ...
PCG sampling of RVT does only works when sampling the first texture layer
UE - Graphics Tools - PCG - Components - Dec 11, 2025The logic for selecting a page table texture in FVirtualTexturePageTable::Initialize() uses the indexing for texture layers (index 0-7) to fetch from the page table textures (index 0-1). All RVT for ...
Crash when adding Actor Array Element to a Sequencer Event Struct
UE - Anim - Sequencer - May 25, 2017Crash when adding Actor Array Element to a Sequencer Event Struct Error message: Assertion failed: 0 [Link Removed] [Line: 56] Source Context: 42 N = FName(*StringName); 43 ...
[CrashReport] UE4Editor_Core!FText::FText() [text.cpp:194]
Tools - Aug 22, 2017This is a regular crash occurring in 4.16 and 4.17. The callstack is nearly identical to [Link Removed], which was fixed in 4.15 (different error message though). User DescriptionsImporting Files ...
Crash when changing r.MaterialQualityLevel when FastGeo plugin enabled in cooked build
UE - World Creation - Worldbuilding Tools - Sep 5, 2025The engine crashes when the r.MaterialQualityLevel is changed in a cooked game that uses the FastGeo Streaming Plugin. The crash doesn't repro with the same steps in Editor, just in a cooked build. ...
AI Pawn Sensing component cannot see and hear at the same time
UE - AI - Mar 12, 2015Hear events are never fired while See events are fired. They are mutually exclusive, with See events taking priority if both happen. ...
LevelEditor: "Replace Actor" marks level as dirty even when using external actors
UE - World Creation - Worldbuilding Tools - Jul 15, 2024When using external actors, adding/removing/replacing/editing an actor instance inside a level does not cause any modification to the Level package, which helps reduce contention for the map file on ...
ISM + WPO = broken motion vectors?
UE - Graphics Features - Nov 5, 2024Instanced Static Meshes will have incorrect velocity if a Material uses World Position Offset. Fixed WPO in a material causes significant velocity on the ISM. This was also replicated in //UE5/Rele ...
[CrashReport] UE4Editor_Slate!TAttribute<FText>::Get() [attribute.h:130]
UE - Editor - UI Systems - Slate - Jul 13, 2017This is a common crash affecting users in 4.16 User DescriptionsI imported an FBX and the editor crashed.alembic import from brekelwhats wrong with the ue4 alembic importer? Source Context 120 ...
[CrashReport][Crash] Engine!FSceneViewport::UpdateViewportRHI() [SceneViewport.cpp]
UE - Rendering - RHI - May 29, 2026#200 crash out of 2101 in UE 5.8 on Windows#34 crash for UE - Rendering - Architecture in UE 5.8 on Windows#20 crash for UE - Rendering - Architecture - RHI in UE 5.8 on WindowsAssertion failed: IsI ...