Crash reimporting a skeletal mesh with less Material IDs than on first import

NOTE: Does not occur in 4.16, entered this to find a fix for licensee to integrate. Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 633] Array index out o ...

NavLink Proxy CHILD ACTOR stops working in a Packaged and Standalone game

UE - AI - Oct 5, 2017

NavLink Proxy CHILD ACTOR stops working in a Packaged and Standalone game. Works as expected in PIE. Licensee Description: Force Rebuild on Load is not called and the nav links as child actors do ...

Mover | FStanceModifier adjustment teleport on Crouch/Uncrouch can fail when child components intersect world

UE - Gameplay - Player Movement - Mover - Feb 3, 2026

Context When crouching and uncrouching with Mover’s DefaultMovementSet, the pawn capsule’s half height is changed. This behavior mimics the CharacterMovementComponent. To ensure the pawn’s feet sta ...

Unable to build marketplace code plug-in

UE - Foundation - Cpp Tools - UnrealBuildTool - May 17, 2022

Fix for [Link Removed] sets the RuleAssembly in the Marketplace plugin to ReadOnly. This has prevented the plugin binaries from being compiled. Change the readonly flag as shown in the following co ...

In the level editor, when configuring a component that is part of an actor blueprint, adding entries to a TMap with C++ enum keys results in duplicate keys and an incorrect warning popup.

UE - Editor - Workflow Systems - Jan 22, 2026

Note: This started happening in UE 5.4 and persists up to latest. It is probably related to [Link Removed] Closed ([Link Re ...

[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 ...

[CrashReport] UE4Editor_ShaderCore!FVertexFactory::Set() [vertexfactory.cpp:190]

UE - Graphics Features - Nov 17, 2017

This is a common crash in the 4.18 release. It is the exact same callstack (and crashGroup) as in [Link Removed], although that Jira had specific repro steps and was confirmed fixed in 4.18.0. The ...

Crash when building lighting while in PIE

UE - Graphics Features - Feb 21, 2017

NOTE: This issue is similar to (same callstack) as [Link Removed], however this issue is still occurring in 4.15.0. Error Message: Access violation - code c0000005 (first/second chance not availab ...

[AI] EQS incorrectly sorts when auto-sort in single-item mode when there is only one filtering and one scoring test.

UE - AI - EQS - Dec 14, 2021

EQS places a cheap filter as the last step of a query when using auto-sort for single item results if there is only one filter. Found via [Link Removed] which is quoted below:Environmental Query sys ...

FBX naming conflicts causing collision to not import correctly.

UE - Editor - Content Pipeline - Import and Export - Feb 17, 2025

For our static mesh pipeline we have group nodes in Maya that use the name of the asset. Under that we have a mesh that also has the name of the asset. We may also have collision as well so a typica ...