Create Session does not work in a packaged game from any project that has used C++

UE - Networking - Dec 28, 2015

After adding C++ to a content-only project, Create Session no longer works in a packaged game. The following warning appears in the log: LogScript:Warning: CreateSession - Invalid or uninitialized ...

[CrashReport] UE4Editor_Engine!FAnimNotifyEvent::IsBranchingPoint() [animtypes.cpp:86]

OLD - Anim - Aug 29, 2017

This is a common crash occurring in the 4.17 release. Users have not provided any descriptions of their actions when the crash occurred. Source Context 72 float FAnimNotifyEvent::GetDurati ...

ShooterGame Crashes on Exit on iOS Due to Exhausting Real Time Allowance

UE - Platform - Mobile - Jul 30, 2018

When closing ShooterGame on an iOS device, the application crashes due to "exhausting the real time allowance of 5.00 seconds". This issue is NOT a regression for //UE4/Dev-Networking as it is also ...

Indirect lighting samples incorrect if duplicated levels placed in same persistent level

UE - Graphics Features - Aug 29, 2017

Indirect lighting samples were not made correctly when building lighting with umap duplicated via the content browser and registering both source and destination as sublevels in one map. ...

[CrashReport] UE4Editor_UMG!UButton::SynchronizeProperties() [button.cpp:62]

UE - Editor - UI Systems - Sep 7, 2017

This is an infrequent but longstanding crash that has occurred since at least 4.13 and affected more than 350 users. User DescriptionsI using widget bp. I Try moving blur mistake same time press ct ...

Copying a grouped MaterialInstanceParameterDetail property that has spaces on it's name does not enclose it in double quotes, and later pasting won't work as expected

UE - Rendering Architecture - Materials - Aug 24, 2025

Copying a grouped MaterialInstanceParameterDetail property that has spaces on it's name does not enclose it in double quotes, and later pasting won't work as expected. The licensee noticed this in a ...

Editor 'Build All Levels' discards Volumetrics Lightmaps in persistent level

UE - Graphics Features - May 14, 2025

Building the level or lightmaps can clear the volumetric lightmap. In 5.5, this requires you to perform a full build, or a lighting only build with a BSP brush in the scene. In 5.6, all level build ...

Ensure triggered with multiple AddInstance() calls for InstancedStaticMeshComponent

UE - Graphics Features - May 20, 2016

Adding multiple instances to instance static mesh component in a code class causes an ensure to trigger when an instance of the class is added to the level. ...

Using dynamic bindings in a code class will result in the bindings becoming a permanent part of any Blueprint created from that class if a hot reload is performed.

UE - Foundation - Core - Mar 26, 2015

If dynamic bindings are being used in a custom code class from which Blueprints are derived, any hot reload will make the bindings a permanent part of the Blueprint and they cannot be removed or cha ...