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 ...

Internal Compile error received from rearranging Format Text nodes

UE - Gameplay - Blueprint - Dec 18, 2014

Internal Compile error received from rearranging Format Text nodes Output Log of Error: LogBlueprint:Error: [compiler] Error Internal compiler error inside CreateExecutionSchedule (site 2); please ...

Pressed event triggered after calling FlushPressedKeys while holding the button

UE - Gameplay - Input - Oct 2, 2024

This is an issue related to the behavior of the FlushPressedKeys function when called manually while a button is held. Once the function is called in C++, a Pressed event gets triggered even though ...

Pre-UE5 serialized FVariant FVector data corruption when deserialized in UE5

UE - Framework - LWC - Jan 15, 2024

FVariant is a struct that implements a union of data types, including FVector. When assigning an FVariant an FVector value in engine versions UE 4.27 or earlier, the FVariant will deserialize incorr ...

World Source in Take Recorder does not record auto-tracked actors properly

UE - Virtual Production - Tools - Take Recorder - May 23, 2025

The Take Recorder plugin allows for multiple sources to be recorded during gameplay. The World Source is expected to record everything in the level when the Autotrack Actors option is enabled. Once ...

Physics Linear Velocity functions from UPrimitiveComponent always return (0,0,0) velocity

UE - Simulation - Physics - Jul 30, 2024

In Unreal Engine version 5.4, all Physics Linear Velocity functions inside PrimitiveComponent class are returning always a velocity of (0,0,0), even if the Body Instances are moving. This was workin ...

Crash retargetting AnimBP with "Allow remapping to existing assets" enabled

OLD - Anim - Aug 24, 2016

4.12 version of the crash: [Link Removed] Error message: Assertion failed: (Index >= 0) & (Index < ArrayNum) [Link Removed] [Line: 833] Array index out of bounds: 1 from an array of size 0 Sourc ...

[CrashReport] UE4Editor_Renderer!FGlobalShader::SetParameters<FRHIPixelShader * __ptr64,FRHICommandList>() [globalshader.h:134]

UE - Graphics Features - Jun 29, 2016

This JIRA was created from crash reports submitted by users due to it being one of the top crashes occurring in 4.12.4 This might be a regression because the crash has only just started in 4.12.4. ...

Ensure triggered when creating Scene Proxy for GroomComponent

UE - Rendering Architecture - RHI - Apr 30, 2025

When a room component is added in C++ via the actor constructor, an ensure is triggered from precaching and the groom component. Behavior also observed on UE5/Release-5.5, CL: 40988944 ...

Hot reload causes placed actor to lose variable references

UE - Foundation - Cpp Tools - Hot Reload - Nov 9, 2017

Preforming a hot reload causes placed actors to lose code based variable settings. More repro steps: 1. Open UE4Editor.exe 2. Create a First Person Code project 3. Build the project for Developme ...