Crash Importing Skeletal Mesh LODs with a lot of morph targets

OLD - Anim - May 18, 2016

Crash Importing Skeletal Mesh LODs with a lot of morph targets Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 785] Array index out of bounds: 2 from an ar ...

When using Perforce, saving a level over another leaves the target umap file as "marked for delete"

UE - Editor - Mar 11, 2025

When working on a level asset and using command "File – Save Current Level As..." to save it over a different level asset, the engine first deletes the target level (that's going to be overwritten) ...

[CrashReport] Assertion failed: TaskDataArray.Num() == Exporter->VolumetricLightmapTaskGuids.Num()

UE - Graphics Features - Lumen - 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, but at least two of the affected projects are being creat ...

5.5 Static Mesh Import Pipeline Regression

UE - Editor - Content Pipeline - Import and Export - Apr 25, 2025

This question was created in reference to: [Link Removed] This post references the first post because this problem was not discovered till now. I think it was masked because the issue appears to be ...

Controller input changes for network players based on which window has focus

UE - Gameplay - Input - May 23, 2016

When testing networked multiplayer with two controllers, if the server window (editor) has focus, controller 1 controls the server character and controller 2 controls the client character. If the c ...

Launching QAGame for HTML5 creates an 'uncaught exception: out of memory'.

UE - Platform - Mobile - Jan 18, 2017

Launching onto HTML5 opens the browser to Uncaught Exception: out of Memory After running it on a 64-bit browser, the following is printed:uncaught exception: abort("Cannot enlarge memory arrays. E ...

[CrashReport] UE4Editor_UnrealEd!FEdGraphUtilities::PostProcessPastedNodes() [edgraphutilities.cpp:138]

UE - Gameplay - Blueprint - Jan 24, 2017

This Jira was created from CrashReports submitted by the public due to the high number of occurrences. Descriptions from users are provided below. Error message: Access violation - code c0000005 ( ...

SDF/Mesh Cards do not follow material settings applied on static meshes.

TM - Core - Feb 4, 2025

Building SDF and Mesh Cards require material properties (2 sided and blend mode) applied on Static Mesh to be known at Static Mesh build time. If not, it may leads to rendering artifacts: Reflectio ...

Level Instance Property Override: Actor::Tags overridden pre-CS but clobbered by RerunConstructionScripts with no post-CS re-apply

UE - World Creation - Worldbuilding Tools - May 4, 2026

Summary When using the Level Instance Property Override system, overrides applied to `AActor::Tags` are silently lost for Blueprint actors whose Construction Script assigns or appends to `Tags`. The ...

Paper2d Plugin Content Missing from Content Browser

UE - Gameplay - Paper2D - Nov 21, 2016

There are a number of assets/content missing from the Paper2D plugin content within the Content Browser. Whether you create a new 4.14 project or upgrade from a previous version, these assets are r ...