AttachRootComponentToActor being used over a network can cause an Ensure (previously an Assertion) to be triggered.

UE - Gameplay - Jan 11, 2016

This is a continuation of [Link Removed]. The previous ticket changed an Assertion to an Ensure in order to stop a crash from occurring, and stated that a more complete fix would be coming in 4.10. ...

Asset values change when the Editor is out of focus when using Maya or Web Browser

Tools - Jul 18, 2018

When switching between any open software (Maya, web browser) and UE4 while Simulation is running, sometimes the values change on the asset and it starts to oscilate between <-0.6,0.6> or any other s ...

Fog Does Not Behave As Expected in Splitscreen

UE - Graphics Features - May 25, 2018

This bug seems to repro very inconsistently for me, but I've seen it affect Atmospheric Fog and Exponential Height Fog, and reproduced in 4.18.3, 4.19.2, and Main CL 4093338. I've attached Config fi ...

Duplicating / Moving (to another level) an actor with a Hierarchical Instanced Static Mesh component causes a crash

UE - Graphics Features - Nov 14, 2016

When you have an actor with a Hierarchical Instanced Static Mesh component that has a Static Mesh set and is populated with at least 1 instance and then duplicate it or move it to another level, it ...

Users are unable to create projects when the default project location is a networked drive

UE - Editor - Workflow Systems - Oct 23, 2024

There have been multiple reports of this issue, particularly from schools, over the last 10 years:https://forums.unrealengine.com/t/invaild-folder-path-with-network-user-drives/283475https://forums. ...

Video material previews incorrectly on Mac

TM - Rendering - Apr 3, 2025

Received multiple reports of users on Mac computers experiencing issues previewing video materials in Twinmotion 2025.1. When adding video materials to the scene, the scale seems to be incorrect an ...

Inconsistent Prioritization of Navigation Modifiers

UE - AI - Dec 12, 2016

When working with Nav Modifiers in a level that contains objects that have a custom Nav Area class, the prioritization of the modifiers is not consistent. If you notice in the attached project, so ...

Planar Reflection with Exponential Height Fog flickers on iOS

UE - Platform - Mobile - Oct 28, 2016

Planar Reflections have noticeable gaps in the reflection of the exponential height fog for the scene that will flicker as the camera moves. Attached ipa link and test project. [Link Removed] Te ...

Auto Reimport crash with some file paths

UE - Editor - Content Pipeline - Import and Export - Dec 14, 2016

Auto Reimport source paths can cause a crash with the editor. I couldn't narrow down in my limited testing what would cause the crash vs what would not with these file paths. The one in my attached ...

Matinee movie recording is broken in 4.10

Tools - Dec 18, 2015

When trying to record a movie from a matinee in 4.10, it can fail for a number of reasons: 1. The folder does not exist 2. The cinematic view modes do not take effect 3. Trying to record a streamin ...