Unreal Engine Issues
Unreal Engine Issues
Assertion failed: (Index >= 0) & (Index < ArrayNum) when importing large Alembic file
UE - Editor - Content Pipeline - Datasmith - Importer - May 3, 2022Regression testing done on //UE4/Release-4.27.2 CL-18427296 and this issue did occur. [Link Removed] [Link Removed] Below is snips of customers description and proposed workaround:Importing alembi ...
[UDN - 00707230] DetailLayoutHelpers ensure when using VisibleAnywhere Instanced properties
UE - Editor - Workflow Systems - Jan 11, 2024From UDN Description Hello, there's an ensure that's firing in `DetailLayoutHelpers.cpp#137`: [Start code block] ensure(PropertyNodeMap.ParentProperty == CurObjectNode); [End code block]when ...
Crash when destroying a pawn on the client
UE - Networking - Jul 6, 2015Crash when destroying a pawn on the client. Reproduced in 4.8.1 and Main (//depot/UE4/Promotable-CL-2610743). This is a regression: the crash does not occur in 4.7.6 Crash Report: [Link Removed] ...
Unexpected behavior when Actor Parenting in the World Outliner of a WP map
UE - World Creation - Worldbuilding Tools - World Partition - Nov 23, 2021Licensee reports the following in the UDN: There seems to be some other erratic behavior when using parenting in world outliner (i.e. drag and drop one actor on another one in world outliner).Since ...
[CrashReport] UE4Editor_Engine!LoadSpecialMaterial() [unrealengine.cpp:1523]
UE - Graphics Features - Nov 10, 2017This is a longstanding crash that has occurred for more than 200 users since at least 4.13. Based on user descriptions this appears to permanently corrupt a project. User DescriptionsI just turned ...
Changing the scale of a single HISM instance greatly affects the LOD selection of all instances
UE - Rendering - Architecture - Sep 22, 2025When using ISMs and HISMs, each instance can have its own transform, which can affect the LOD selection of one or more instances. For HISMs in particular, changing the scale of a single instance gre ...
[CrashReport] UE4Editor_CoreUObject!UObjectPropertyBase::Identical() [propertybaseobject.cpp:60]
UE - Foundation - Cpp Tools - Hot Reload - Nov 17, 2016This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Error message: Access violation - code c0000005 (first/second chance not available) Source C ...
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 ...
Backwards-compatibility broken for the CDOs of Python-generated Unreal Types because of missing redirectors
UE - Editor - Workflow Systems - Feb 11, 2025Previously, all Unreal Types generated by python scripts would be created inside package "/Engine/PythonTypes". This was changed by [CL 32478991 in ue5-main branch], which meant to "remove the restr ...