[CrashReport] UE4Editor_Core!FTaskGraphImplementation::WaitUntilTasksComplete() [taskgraph.cpp:1121]

Tools - Apr 5, 2016

This 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: CurrentThreadIfK ...

Static Mesh cooking: Bad mesh description should not crash the cooker

UE - Graphics Tools - Modeling Tools - Mesh Editing - Aug 21, 2023

FStaticMeshRenderData::Cache has the assertion: checkf(Owner->IsMeshDescriptionValid(0), TEXT("Bad MeshDescription on %s"), *GetPathNameSafe(Owner)); This assertion can be triggered by data erro ...

[CrashReport] Crash on Mac due to uncaught exception 'NSRangeException' - NSCFConstantString characterAtIndex

UE - Platform - Apple - Jul 27, 2017

This is a common and longstanding community crash on Mac. Users have not provided descriptions when they crash, so additional information is currently not available. A log file is attached. Callsta ...

[Enhanced Input] Chord trigger fails when its referenced action lives in a lower-priority IMC

UE - Gameplay - Input - May 18, 2026

Summary A UInputTriggerChordAction does not fire when the action it references (the "chording action") is mapped in a different Input Mapping Context with a lower priority than the IMC containing the ...

[CrashReport] Assertion on Mac in FCocoaRunLoopSource

UE - Platform - Apple - Jun 14, 2017

This is a common crash among Mac users in 4.16. It is spread out among many separate CrashGroups, with slight variations in Callstack. Some Example CrashGroups [Link Removed] [Link Removed] [Link ...

[CrashReport] Mac crash - USpeedTreeImportFactory::FactoryCreateBinary()

Tools - Sep 8, 2017

This is an infrequent Mac crash that has occurred for a few users since at least 4.16. Users have not provided any descriptions of their actions when the crash occurred. The callstack shares simil ...

StateTree: While editing State Parameters or exposed properties of a Condition/Task, an ensure() fires when editing inputs of a Property Function bound to an array element

UE - AI - StateTree - Mar 5, 2026

Consider an array property that can be edited in the StateTree editor. This can be a State Parameter or an exposed property of a Condition or Task, for example. Each element of the array can be boun ...

CPF_TextExportTransient and RF_TextExportTransient inconsistent behavior

UE - Framework - Blueprint - May 23, 2024

The TextExportTransient can be specified as a property flag and object flag. Behavior is inconsistent: there are many ways in which an object marked TextExportTransient can still be part of the text ...

Ensure condition failed : SkeletalMeshLocation module on scaled SkeletalMesh

UE - Niagara - Jul 14, 2020

The message in ensure is below LogOutputDevice: Error: === Handled ensure: === LogOutputDevice: Error: Ensure condition failed: (FMath::Abs(1.f - M.GetScaledAxis(EAxis::X).SizeSquared()) <= (1.e-4 ...

Crash in MaterialInstance when deleting a layer

UE - Graphics Features - May 4, 2021

Repro from licensee here - [Link Removed] ...