Unreal Engine Issues
Unreal Engine Issues
The light in the Blueprint Editor's Preview Scene does not respond to any lighting channel but 0.
UE - Framework - Blueprint Editor - Jun 28, 2024In the Blueprint Editor, Primitive Components can be configured to respond to Lighting Channels 0, 1, and/or 2. However, if channel 0 is disabled (even with another one enabled), the Preview Actor's ...
Landscape Splines in Partially Loaded World Partition Levels Can Cause Nanite Landscape Invalidation
UE - Graphics Tools - Terrain - Nov 7, 2025Certain placements of landscape splines in world partition levels can cause Nanite landscape proxies to invalidate, and switch back to their non-nanite version. This happens when specific regions of ...
Exported Particle Emitter Tries to Reference Graphs of Original System
UE - Niagara - Dec 7, 2017User reports that the bug was initially discovered in 4.18 and then reproduced in 4.16 project (attached). Per User: For some reason when exporting this emitter to any other system bugs out. When ...
Packaging fails after changing from Dynamic to Static Nav Mesh Runtime Generation
UE - AI - Feb 8, 2016If you package with Runtime Generation set to Dynamic and then switch to Static and attempt to repackage, the packaging will fail with the following error message.[2016.02.08-16.18.14:511][217]MainF ...
Meshes with scaled root bones pop when entering simulation
UE - Runtime - Simulation - May 15, 2026This issue is fallout from the changes in 33851494. Prior to that, we didn’t get the pop on beginning the sim. The problem appears to be that in USkeletalMeshComponent::PerformBlendPhysicsBones we ...
Visual Studio opens unnecessary windows when adding a new C++ class via the editor's interface
Tools - Oct 25, 2017When adding a new C++ class to a project via the editor's interface, Visual Studio is opened but it ends up opening more than is necessary. Firstly, Visual Studio is opened without focus on the two ...
[CrashReport] UE4Editor_LevelEditor!FMulticastDelegateBase<FWeakObjectPtr>::RemoveAll() [multicastdelegatebase.h:81]
Tools - Oct 26, 2017This is a trending crash in 4.18.0. One case of this callstack occurred in 4.17.1, but then numerous have occurred in 4.18. Users have not provided any descriptions of their actions when the crash ...
Tabbing out of exclusive fullscreen leaves the window & backbuffer in an incorrect state
UE - Editor - UI Systems - Apr 24, 2020With windows 10 there has come some new swap chains, which unfortunately messes some things with regards to fullscreen up. We've fixed a bunch in the renderer (which would downright cause crashes), ...
Possible data loss/corruption when loading levels in editor
UE - Gameplay - Jul 18, 2018Reported behavior: Given Level_A which contains object_X, where object_X references Level_BDeleting object_X causes AssetRenameManger to check if we need to patch up other levelsLevel_B is load ...
Failure to sign when packaging for iOS Distribution when using Remote Compile from a code project on Windows
UE - Platform - Mobile - Feb 20, 2019Packaging for iOS Distribution from Windows using Remote Compile results in a failure during the signing portion. This seems to be caused by a hardcoded "false" for a property that is used to determ ...