Enabling Override Instance Data to a LevelSequencerActor that has a Shot Track can lead to crashing the engine

UE - Anim - Sequencer - Mar 17, 2025

Enabling Override Instance Data to a LevelSequencerActor that has a Shot Track can lead to an Actor being translated really far, or even a crash in the engine. The licensee has encountered a particu ...

[CrashReport] UE4Editor_MovieSceneTracks!UMovieSceneCameraCutSection::GenerateTemplate() [moviescenecameracutsection.cpp:24]

UE - Anim - Sequencer - Oct 30, 2017

This is a somewhat common Sequencer crash that occurs in 4.17 and 4.18. User DescriptionsWas trying to copy and paste a camera movement but something screwed up, I tried to add an already built Cam ...

UMG: RetainerBox with zero-size child returns incorrect LayerId on OnPaint()

UE - Editor - UI Systems - Nov 4, 2025

When a RetainerBox contains a child that for some reason has a desired size of zero, its OnPaint() method can incorrectly return LayerId 0. Afterwards, widgets further down the hierarchy can base th ...

[CrashReport] UE4Editor_MaterialEditor!CastChecked<UMaterialGraphNode,UEdGraphNode>() [casts.h:192]

UE - Rendering - Architecture - Materials - Aug 31, 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: Access violation - code c0000005 ( ...

[CrashReport] UE4Editor_Core!FArchive::SerializeCompressed() [archive.cpp:447]

UE - Foundation - Core - Nov 17, 2016

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Assertion failed: PackageFileTag.CompressedSize == PACKAGE_FILE_TAG_SWAPPED [L ...

Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key causes a memory leak

UE - Framework - Blueprint - Apr 15, 2025

When Calling UBlueprintMapLibrary::GenericMap_Find with a non-existent key, the function construct the default structure in-place on the given pointer without destroying the object. This behavior ca ...

macOS build appears to hang due to UBT deadlocking on ps buffer

UE - Foundation - Cpp Tools - Apr 22, 2021

Licensee reports buffer deadlock issue in System/BuildHostPlatform.cs (lines 283-329). Moving Proc.WaitForExit() to after the for-loop seems to resolve the issue for them.publicoverride ProcessInf ...

[CrashReport] UE4Editor_Engine!ULevel::GetWorldSettings() [level.cpp:1781]

Tools - Aug 22, 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: WorldSettings != ...

"Primitives with unbuilt interactions" not clearing after lighting scene rebuild

UE - Graphics Features - Oct 29, 2021

Regression No, according to affect version 4.26 and 4.27 [2021.10.29-17.01.06:085][830]Primitives with unbuilt interactions: 6[2021.10.29-17.01.06:085][830] Primitive FoliageInstancedStaticMeshComp ...

In BP/Python Editor Utilities, function SetEditorProperty() unexpectedly fails for Actor Reference Properties on External Actors.

UE - World Creation - Worldbuilding Tools - May 19, 2024

As part of the Python and Editor Scripting Tools, it is possible to programmatically set variables in actor instances of the current level just like when using the Details Panel in the Level Editor. ...