Saving Behavior Tree with Blueprint task inheriting from native class invalidates Blackboard key when BP contains a function

UE - AI - Jul 8, 2025

A regression introduced in UE 5.6 causes Blackboard key selectors in Blueprint tasks to become invalid when the Blueprint inherits from a native subclass of UBTTask_MoveTo (or UBTTask_BlackboardBase ...

[CrashReport] Assertion failed: !bRequireNormalization - UE4Editor_Landscape!ULandscapeComponent::ReplaceLayer()

UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017

This is a common crash affecting users in 4.16, and has occurred since at least 4.14. Over 200 unique users have been affected, though they have provided little information. User DescriptionsI am a ...

Sub-world partitions do not properly handle partial editor loading as world partition standalone level instances' spatially loaded actors do not get loaded even when the Level Instance is force loaded or loaded in by region.

UE - World Creation - Worldbuilding Tools - World Partition - Aug 19, 2025

Context Level Instancing is a level-based workflow designed to improve and streamline the level editing experience. In a standalone Level Behavior, when the Level Instance Actor is loaded through it ...

When using object lit by the Indirect Lighting Cache sometimes the cache will not load correctly for movable objects when a level is streamed that contains a landscape

UE - LD & Modeling - Terrain - Landscape - Jun 26, 2015

When setting up a scene with a persistent level and any sublevel that contains a landscape that is loaded via load stream level node in the level BP can cause the ILC to not be correctly assigned fo ...

[CrashReport] UE4Editor_LevelEditor!FLevelEditorActionCallbacks::Paste_CanExecute() [leveleditoractions.cpp:1602]

UE - Gameplay - Blueprint - Jan 17, 2017

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: GEditor->GetSele ...

Using Execute Console Command in a custom Game Instance causes Standalone Game to crash

UE - Gameplay - Blueprint - Jan 15, 2015

Using Execute Console Command in a custom Game Instance causes Standalone Game to crash. Also occurs in 4.6.1: CL-2386410 and 4.7 Preview: CL-2403078 Crash Report: [Link Removed] Call Stack:UE4Ed ...

DynamicMaterialParameters Niagara module resets write flags on emitter update

UE - Niagara - Feb 4, 2026

When using the DynamicMaterialParameters Niagara module in UE 5.6, 5.7, and UE5-Main (CL 50298778), updating an emitter causes Boolean values, such as Index0Float0Write, to reset to default values, ...

Crash when saving after resetting Instanced array element via Property Matrix on placed actors

UE - Editor - Nov 21, 2025

When an Actor Component contains an Instanced UObject array marked EditDefaultsOnly, adding a new element to the Blueprint defaults correctly updates the Blueprint and its own Property Matrix. Howev ...

Crash after setting a key on a Rotation Track, then trying to right click the key with Transform track collapsed

UE - Anim - Sequencer - Aug 3, 2016

Error message: Access violation - code c0000005 (first/second chance not available) Source Context: 336 337 if (bHasRotationKeys) 338 { 339 TSharedRef<FStru ...

An InstancedStaticMesh component set to Stationary doesn't register overlaps

UE - Simulation - Physics - Dec 16, 2016

An InstancedStaticMesh component set to Stationary doesn't register overlaps. However, overlaps are registered on Static and Movable. There is also an issue where actors that start overlapped with ...