iOS movie (mp4) has no sound in the playback.

UE - Platform - Mobile - May 16, 2017

There is no sound in the movie play in iOS, built with 4.16 GitHub source code version. you can simply reproduce using attached sample project. This is reproduced in iPhone 5s(10.3.1) iPhone 6(iOS ...

Crash when using automated groom import

UE - Editor - Content Pipeline - Import and Export - Jan 5, 2021

UDN customer reported that using automated groom import through Blueprint was crashing. This can probably be reproduced with a Python script using an asset import task with the automated flag set to ...

City Sample - Parked Cars, Traffic, and Crowds do not spawn while in PIE

UE - AI - Mass - May 1, 2023

Repro Rate 10/10 Issue is a Regression as it doesn't occur in 5.1 Parked Cars, Traffic, and Crowds spawn in as expected when launching the project in Game Mode or a Packaged Build Going into the ...

Using "Replace variable with..." does not mark a blueprint as needing compilation

UE - Gameplay - Blueprint - Jan 4, 2016

Using "Replace variable with..." does not mark a blueprint as needing compilation. Reproduced in 4.9.2 binary, 4.10.1 binary, and Main 4.12 (CL 2813214). This is not a regression; the same bug appe ...

Cannot Increment an Element of an Array

UE - Gameplay - Blueprint - Apr 15, 2016

Attempting to increment the value of an array element does not seem to work, and instead returns the original value that was passed into the increment int node. Found in 4.11.1 binary. Reproduced i ...

Run command fails launching onto iOS from Mac with Error_DeviceOSNewerThanSDK on Xcode 8.3.3

UE - Platform - Mobile - Jun 9, 2017

Xcode version is 8.3.3 and device OS version is 10.3.2Error Launch failed! Failed to launch on device. Make sure your install of Xcode matches or is newer than the OS on your device. Tested on i ...

WorldPartitionConvertCommandlet hits an assert when converting a persistent level that contains a sub-level with a landscape

UE - World Creation - Worldbuilding Tools - Nov 7, 2025

Context: The Window tab allows a user to open the Levels window in order to add a sub-level to a persistent level. For Unreal Engine 5.0 and beyond, World Partition has made the Levels window obsole ...

Crash When Adding Actor Component Tagged 'Within' to a Game Mode Blueprint

UE - Gameplay - Components - Apr 25, 2016

Crash occurs when attempting to add an actor component c++ class to a game mode blueprint if the actor component is tagged with the Within="GameMode". Found in 4.11.2 binary, reproduced in 4.10.4 ...

Generate Project Files is not automatically run after Switch Unreal Engine Version on Mac

UE - Foundation - Core - Feb 8, 2016

When converting a project to a different version of the engine, the GenerateProjectFiles.command process is not ran as it would be on Windows with GenerateProjectFiles.bat. This can cause issues, es ...

Crash when Toggling Landscape Mode with Hidden Sub-Level containing a Landscape

UE - LD & Modeling - Terrain - Landscape - Oct 28, 2016

A crash occurs when you have a hidden Sub-level containing a landscape and you attempt to toggle the Landscape Mode after re-opening the project. The licensee has authored their own fix for this is ...