Client crashes after second seamless travel when a blueprint manually placed in the world spawns a replicated actor

UE - Networking - Sep 19, 2019

When a user loads into a level that spawns replicated actors using manually placed blueprints twice using ServerTravel with Seamless Travel enabled it will crash. It looks like the engine can't find ...

[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 ...

Animating blueprint mesh duplicates uncontrollably

UE - Gameplay - Components - Apr 15, 2015

When animating within a blueprint of a subclass created in c++, the animating mesh replicates itself uncontrollably. Added to .h: UPROPERTY() UBoxComponent* BoxComp; UPROPERTY() USkeletalMeshCompo ...

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. ...

SCS child scene component instances can be registered out-of-order with non-scene component instances (regression).

UE - Gameplay - Components - Sep 7, 2016

This behavior is a regression in 4.12. Essentially we switched to attaching child components as part of the OnRegister() logic. This caused all root-level SCS components (including non-scene compone ...