Unreal Engine Issues
Unreal Engine Issues
User-defined InstancedStaticMeshComponent subclass misbehave in SCS Editor
UE - Framework - Blueprint Editor - Oct 13, 2025Context Users can create InstancedStaticMeshComponent (ISMC) (blueprint) subclasses. Any ISMC class can be added to an actor blueprint. When a mesh is selected and transforms are added to the Insta ...
Crash when a subsystem calls GetSubsystemArray() on its owner while engine code is iterating on subsystems also obtained through GetSubsystemArray()
UE - Gameplay - Aug 6, 2024In some occasions, engine code iterates over a certain subsystem type by calling FSubsystemCollection::GetSubsystemArray() and then calling some method on all subsystems of the returned array. This ...
NVIDIA 5080 GPU Crash when launching City Sample with DX12
UE - Graphics Features - Lumen - Apr 16, 2025UPDATE This issue no longer reproduces on driver versions 580.88 and higher. City Sample game crashes immediately upon opening with a NVIDIA 5080 with the latest drivers as well as some previous dr ...
Sequencer : Attaching a Possessable to multiple Spawnables across multiple cuts causes incorrect location restoration
UE - Anim - Sequencer - Nov 12, 2021Regression No, according to affects versions 4.27 and 4.27.1 The restore process proceeds in the following order : 1. Remove spawnable actor in first cut (no effect because the actor is already r ...
"FVector contains NaN" on packaged builds for Debug configuration
UE - Graphics Features - Lumen - May 6, 2022Customer Provided Description:This was experienced in UE 5.01 - custom installed engine (No changes to UE code, simply added the Debug build configuration, see the following command): "c:%ue_dire ...
Crash handling: Prevent reports of assertions during shutdown after an assertion
UE - CoreTech - Aug 8, 2024CriticalErrors in FWindowsErrorOutputDevice::Serialize (and other platforms) run some code after the error is detected rather than immediately terminating the process. Some of this other code is spe ...
LoadErrors:Warning: Warning CreateExport: Failed to load Outer for resource when moving Blueprints folder to another folder
UE - Gameplay - Blueprint - Apr 14, 2017There are 3 assets from Content > Blueprints > Missing Types that are failing to be moved over The assets are causing the warnings are:BP_NodeClassIsMissingBP_ParentClassIsMissingTypeBP_PinReferenc ...
Actors disappearing after saving a large number of modifications to world partition maps
UE - Editor - Workflow Systems - Nov 4, 2022From Licensee: "We've encountered a world partition bug where newly created actors go missing in the viewport and Outliner after saving modifications to a large number of actors. This bug is partic ...
Users are unable to create projects when the default project location is a networked drive
UE - Editor - Workflow Systems - Oct 23, 2024There have been multiple reports of this issue, particularly from schools, over the last 10 years:https://forums.unrealengine.com/t/invaild-folder-path-with-network-user-drives/283475https://forums. ...
LayeredBlendPerBone without BlendRootMotionBasedOnRootBone exaggerates root motion
UE - Anim - Runtime - May 27, 2023When BlendRootMotionBasedOnRootBone is false, the LayeredBlendPerBone is aggregating root motion of the child poses ontop of the base pose root motion. (ie. if the first child pose's blend weight i ...