TMap Contains Node Returns False Incorrectly Under Specific Circumstances

Tools - Nov 20, 2019

The Contains node doesn't return an existing row from a data table under specific circumstances. This didn't occur when the struct the data table is based on was made via blueprints or there are mor ...

UClass::SparseClassDataStruct null at editor-time for child blueprints until compile

UE - Framework - Blueprint - May 29, 2024

Child blueprints of a blueprint of a native actor class with sparse data can have an incorrectly null SparseClassDataStruct value, and thus fail to initialzie their SparseClassData. This affects edi ...

[CrashReport] UE4Editor_Renderer!TStaticMeshDrawList<TBasePassDrawingPolicy<FUniformLightMapPolicy> >::GetUsedPrimitivesBasedOnMaterials() [staticmeshdrawlist.inl:868]

UE - Graphics Features - Feb 19, 2016

This Jira was entered due to a high number of occurrences in 4.11 Preview 5. Error message: Assertion failed: !Proxy->IsDeleted() [Link Removed] [Line: 867] Source Context: 853 { 854 ...

[CrashReport] Access Violation - UModelComponent::GetPhysicsTriMeshData() [modelcomponent.cpp:673]

UE - Simulation - Physics - Oct 2, 2017

This is a trending crash coming out of the 4.18 Previews. Users have not provided any descriptions of their actions when the crash occurred. The callstack is similar to [Link Removed], which was ju ...

Non-reflected header files not recognized by UHT

UE - Foundation - Core - Jul 28, 2015

A user adds 3 .h files though Visual studio where the first contains a struct, the 2nd includes the 1st, the 3rd includes the 2nd and tries to make a variable of the struct declared in the 1st. The ...

[CrashReport] Assertion failed: Array index out of bounds - GetPhysicsTriMeshData() [modelcomponent.cpp:688]

UE - Simulation - Physics - Oct 30, 2017

This is a semi-common crash that has occurred since at least 4.17.1. The callstack is nearly identical to [Link Removed], which was fixed in 4.18.0, however the error message and source context are ...

Assertion failed: (Index >= 0) & (Index < ArrayNum) when importing large Alembic file

UE - Editor - Content Pipeline - Datasmith - Importer - May 3, 2022

Regression 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 ...

Children of editor-only actors do not maintain correct transforms when placed inside level instances for PIE and cooked builds

UE - World Creation - Worldbuilding Tools - Level Instances - Oct 20, 2025

We have found an issue where children of editor-only actors get wrong transforms in PIE and cooked builds when placed inside level instances. This affects both engine version 5.5 and 5.6. The issue ...

Crash when trimming animation and then undoing action

UE - Anim - Runtime - May 30, 2023

Repro rate: 3/3 times This is a regression as the issue does not occur in 5.1.1  ...

Exception on missing file during GC in horde storage

UE - Foundation - Horde - Storage - May 7, 2025

During GC, if a file was manually deleted (but the storage system is still track), GC can erroneously fail (and never remove the reference). This causes a backup in GC, putting the whole algorithm i ...