Unreal Engine Issues
Unreal Engine Issues
CheckCompilingPSOs assert in FMaterialPSORequestManager::MarkCompilationComplete fires occasionally
Find the root cause and fix it. Potential issue based on logs:New RequestA is created in PrecachePSOs and its collection task is dispatched and finishedRequestA is waiting for compilation taskReque ...
SetCollisionProfileName and SetCollisionEnabled aren't working in Construction Script
UE - Simulation - Physics - Dec 5, 2019This is a regression from 4.22.3 (CL-7053642) where this setup executed as expected. Toggling Collision Profiles in 4.23.1 (CL-9631420) and onward do not affect the Static Mesh and it acts as if it ...
[CrashReport] Access violation in UE4Editor_Engine!TOctree<TVolumeLightingSample<3>
UE - Graphics Features - Jun 14, 2017This is a common crash in the 4.16 release. The callstack for the issue is essentially the same as [Link Removed], however that issue had confirmed repro steps and was verified fixed for 4.16.0. A ...
DDC corruption creates incorrect pasted topology when using Landscape Copy / Paste Tool
UE - LD & Modeling - Terrain - Landscape - Apr 3, 2017I noticed that the copy and pasted section of the level was being painted while I was painting a nearby section of the level. This weird yellow color appeared and I undid and redid the paint to make ...
Morph target normals not correctly applied when imported as LOD 0
UE - Editor - Content Pipeline - FBX - Nov 27, 2025This is a regression since 5.5 with skeletal meshes where morph target normal/tangent deformation only works when a mesh is imported as a LOD of an existing skeletal mesh, but not when imported as L ...
Virtual textures flicker if physical pool is oversubscribed
UE - Graphics Features - Feb 24, 2021If a virtual texture physical pool becomes oversubscribed the current behavior is: Log a one time only warning: ''Failed to allocate VT page from pool...' Continue to evict the least recently used t ...
World Partition - Deleted actors can become unloaded prior to saving
UE - World Creation - Worldbuilding Tools - World Partition - Apr 11, 2025In world partition levels, deleted actors can become unexpectedly unloaded prior to saving, causing loss of work. Specifically, this issue occurs after the undo history has been cleared (either manu ...
When using 'r.VT.SplitPhysicalPoolSize 64' with nanite meshes, mesh painting does not update in real time (only updates after stroke finished), duplicates mesh painting across separate instances of a mesh, and sometimes doesn't show up in PIE.
UE - Rendering Architecture - Mar 3, 2025When using Mesh Painting on nanite meshes in 5.5 with 'r.VT.SplitPhysicalPoolSize' set to non-zero values (e.g. 16, 64), several issues occur, such as: 1. Painting doesn't update in real time (only ...
Typo in "BaseEditorSettings.ini": under section [/Script/UnrealEd.ContentBrowserSettings], key "DisplayPluginFolder" (singular) should read "DisplayPluginFolders" (plural).
UE - Editor - Workflow Systems - Oct 11, 2025File "<ENGINE_PATH>/Engine/Config/BaseEditorSettings.ini" contains the following setting: [/Script/UnrealEd.ContentBrowserSettings] ; Whether to display the game project plugins in the Content Brow ...
[CrashReport] Fatal Error: Outstanding reference to module 'Renderer' while trying to unload it
UE - Graphics Features - May 30, 2017This crash was previously being tracked in [Link Removed] with a generic "Assertion failed: ModuleInfo.Module.IsUnique()" error message. Ben.M updated that with CL 3376654 and commented: "This cou ...