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 ...

[CrashReport] USpeedTreeImportFactory::FactoryCreateBinary()

UE - Editor - Content Pipeline - Import and Export - Sep 19, 2017

This is a common and longstanding SpeedTree import crash that has occurred since at least 4.14 for over 100 users. This seems to be the same issue as a previous Jira from 4.10 which was closed wit ...

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 - Runtime - Character - 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 ...

[CrashReport] UE4Editor_LevelEditor!SLevelViewport::SaveConfig() [slevelviewport.cpp:2019]

Tools - Sep 6, 2016

This JIRA is being entered as a result of it being one of the top crashes in 4.13.0. Error message: Access violation - code c0000005 (first/second chance not available) Source Context: 2004 ...

Unable to build marketplace code plug-in

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

Fix for [Link Removed] Closed sets the RuleAssembly in the Marketplace plugin to ReadOnly. This has prevented the plugin bi ...

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 - 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 ...