Unreal Engine Issues
Unreal Engine Issues
ChaosCacheManager is not reproducing Collision Events the second time you Record and Play
UE - Simulation - Physics - Mar 28, 2025ChaosCacheManager (CCM) is not reproducing Collision events the second time (and onwards) we record a Geometry Collection (GC) breaking session. Particles set to track Collision Events correctly fol ...
Crash When Typing a Node Comment and Hovering Over the Alignment Option
Tools - Apr 5, 2016Error message: Assertion failed: ParentIndex != INDEX_NONE [Link Removed] [Line: 512] Source Context: 499 } 500 501 return Menu; 502 } 503 504 ...
Editor crashes when changing skeletal mesh if another skeletal mesh component is attached when using master pose node
OLD - Anim - Jan 27, 2020The crash only occurs if the additional skeletal mesh component is used with Set Master Pose Component (see ToggleAttach function in the TopDownCharacter BP). It doesn't seem to matter what mesh we' ...
[CrashReport] UE4Editor-CoreUObject.dylib!UObject::Rename()
UE - Platform - Apple - Sep 14, 2017This is an infrequent Mac crash that has occurred for a few users in 4.17. Users have not provided any description of their actions when the crash occurred. The callstack has a few similarities to ...
[CrashReport] ULevel::GetWorldSettings - UMaterialFunctionThumbnailRenderer::Draw
Tools - Oct 30, 2017This is a common crash that has occurred since at least 4.16. The callstack is nearly identical to [Link Removed], which appears to be fixed in 4.18; and [Link Removed], which has not. The differen ...
Structs cause packaging to fail when Blueprint Nativization Method is set to "Inclusive"
UE - Gameplay - Blueprint - Apr 26, 2017Structs cause packaging to fail when Blueprint Nativization Method is set to "Inclusive" Note: Appears to be a regression (worked in 4.15.1) Error example: UATHelper: Packaging (Windows (64-bit)) ...
Deadlock when running an asset validator commandlet with async skeletalmesh build
UE - Editor - Content Pipeline - Asset Build - Mar 10, 2023[External Code] UnrealEditor-Core.dll!FEventWin::Wait(unsigned int WaitTime, const bool bIgnoreThreadIdleStats) Line 1515 C++ UnrealEditor-Engine.dll!FAsyncTaskBase::WaitCompletionWithTimeout( ...
[CrashReport] Assertion failed: !bIsReentrant - UE4Editor-UnrealEd.dylib!SaveWorld()
UE - Platform - Apple - Jul 27, 2017This is a common crash on Mac in 4.16 and has occurred since at least 4.14. User DescriptionsI added a character to a blank map and tried to save it. Callstack from LogLogEditorViewport: Clicking ...
Niagara Scalability Crash When Processing Significance
UE - Niagara - Jun 4, 2025Method FNiagaraScalabilityManager::ProcessSignificance() iterates on indices from Context.SignificanceIndices and uses them to access the State and ManagedComponents arrays. It can then decide to cr ...
MovieRender Pipeline Skips Output Frames during GC
UE - Anim - Sequencer - Jun 8, 2020This is being seen in the wild... can release a temporary fix until 4.26 when we can change the headers and fix it for real. ...