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 during Datasmith file import when not using Keep Hierarchy

TM - Interoperability - Jun 24, 2025

Reported to support. The user has reported that one of their .udatasmith files will consistently crash in TM 2025.1.1 during import. This was consistently reproducible when importing using Collaps ...

Animated characters may appear in A pose after loading a file with Path Tracer enabled

TM - Rendering - Mar 12, 2025

When saving a file with Path Tracer enabled at the time of save, animated characters will appear in an A pose state. This will persist until Path Tracer is disabled. Occurs in Twinmotion 2024.1.2 a ...

A warning is needed for turning off "Update Navigation Automatically", large nav meshes can cause crashes

UE - AI - Jul 7, 2015

A warning is needed before allowing users to uncheck update Navigation Automatically. A user has done so and then created a nav mesh that was 1,000,000 by 1,000,000 in size and they can no longer op ...

Bug in ULevel::FixupActorFolders.

There is a potential bug in ULevel::FixupActorFolders() in the FixDuplicateFolders section: Suppose you have a folder hierarchy that looks like this:A B(1)B(2) C(1)B(3) C(2) where the letters ...

[CrashReport] UE4Editor_CoreUObject!UObjectBase::IsValidLowLevelFast() [uobjectbase.cpp:294]

UE - Foundation - Core - Aug 22, 2017

This is a common crash in the 4.16 and 4.17 releases. User DescriptionsWriting a custom component in C++. Hotcompiled it through VS2017. Had the BP editor open with a class derived from that compo ...

Meta Allowed Class Doesn't Allow All The Included Classes

Tools - Dec 24, 2019

The Meta Allowed Classes specifier doesn't allow the user to assign anything of the second type. Found in 4.24.1 CL#10757647 Reproduced in 4.23.1 CL#9631420, 4.25 Main CL#10868506 ...

Plugins are not creating shipping versions on package on Mac 4.23 Preview

UE - Foundation - Cpp Tools - Jul 15, 2019

When you try to package a plugin on Mac in 4.23.0 Preview 1 there is no Shipping folder generated. This was verified to not happen in 4.22.3 (via Epic Launcher). Found in 4.23.0 Preview 1 CL# 72363 ...

Interchange: Forcing "Bind Pose Time Zero" to true doesn't always give good result

UE - Editor - Content Pipeline - Import and Export - Nov 6, 2024

When using the legacy fbx importer with time zero option to true the skinning is good. So its a regression. Would be awesome if it can be fix in 5.5.1 ...

Traveling away from, then back to the original map in multi-process PIE with the editor as a client causes an assert

UE - Networking - Mar 28, 2016

An assert is triggered in this case because in multi-process PIE, if the editor is a client, the PIEInstance of the world context remains at -1 (see UEditorEngine::PlayInEditor). If this client inst ...