Unreal Engine Issues
Unreal Engine Issues
FNiagaraScalabilityManager incorrectly reactivates a NiagaraComponent that was deactivated by runtime user code
UE - Niagara - Scalability - Oct 1, 2025Context: The Niagara System is the primary tool to do visual effects inside Unreal. Niagara systems can be culled due to distance. Problem: Once a deactivated Niagara System is culled due to distan ...
[CrashReport] Failed assert during BP compilation (trying to call a default delegate) (UE4Editor_KismetCompiler!FScriptBuilderBase::EmitFunctionCall() [kismetcompilervmbackend.cpp:1216])
UE - Gameplay - Oct 27, 2017This is a trending crash coming out of the 4.18 release. User DescriptionsI tried to call an Event Dispatcher (which is assigned in the Level Blueprint) in the Construction Script of the Blueprint ...
[CrashReport] Mac/Metal Intel compiler crash - UE4Editor-MetalRHI.dylib!CreateMTLRenderPipeline()
UE - Graphics Features - Oct 27, 2017Mark S: This is an Intel compiler failure on macOS 10.12.6. Callstack from LogAssertion failed: [File:/Users/build/Build/++UE4+Release-4.18+Compile/Sync/Engine/Source/Runtime/Apple/MetalRHI/Privat ...
Bug in StringTemplate.cpp related to modulo operator in MaterialTemplate.ush (code fix provided)
UE - Rendering Architecture - Materials - Jun 25, 2024Shader Template files like MaterialTemplate.ush do not submit previous chunks when encountering a `%` character, unless that `%` character is `%s` or `% {...} `. Because the error is happening ...
[CrashReport] UE4Editor_CoreUObject!StaticAllocateObject() [uobjectglobals.cpp:2153]
UE - Anim - Sequencer - Jun 3, 2016Really close to the repro steps for [Link Removed] Same repro steps produced the following Buggs along with this one: [Link Removed] [Link Removed] Error message: Fatal error: [Link Removed] [Lin ...
[CrashReport] UE4Editor_PropertyEditor!SDetailSingleItemRow::OnArrayDrop() [sdetailsingleitemrow.cpp:172]
Tools - Oct 10, 2017This is a trending crash coming out of the 4.18 previews. Users have not provided any descriptions of their actions when the crash occurred. The callstack shares similarities to [Link Removed] whi ...
Reversed Animations don't play properly using Skeletal Mesh Pose and animations with Keep State in Sequencer
UE - Anim - Sequencer - Nov 26, 2018The bug seems to only reproduce when setting animations in sequencer and only if the animations are set to "Keep state". Setting them to "restore default" makes the reversed animation play correctly ...
Crash adding an AnimComposite to itself
OLD - Anim - Feb 24, 2017Error message: Stack overflow - code c00000fd (first/second chance not available) Source Context: 74 void UAnimComposite::GetAnimationPose(FCompactPose& OutPose, FBlendedCurve& OutCurve, c ...
[CrashReport] UE4Editor_AlembicLibrary!AbcImporterUtilities::GenerateSmoothingGroupsIndices()
UE - Gameplay - Aug 5, 2016This JIRA is being entered as a result of it being one of the top crashes occurring in 4.13 Preview 1. Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 833] ...
[CrashReport] UE4Editor_Engine!UAssetImportData::ExtractFilenames() [assetimportdata.cpp:156]
Tools - Sep 7, 2017This is a common crash affecting users in 4.17 and 4.18. User DescriptionsI wasn't able to get my UCX collision to import. Clicked the yellow "return" arrow next to the asset import settings option ...