Packaging fails after changing from Dynamic to Static Nav Mesh Runtime Generation

UE - AI - Feb 8, 2016

If you package with Runtime Generation set to Dynamic and then switch to Static and attempt to repackage, the packaging will fail with the following error message.[2016.02.08-16.18.14:511][217]MainF ...

Runtime memory leak with imported FBXs

Tools - Feb 6, 2017

When a certain kind of mesh is loaded/unloaded at runtime from transitioning levels, the amount of unfreed memory of the game will steadily increase. There is some natural fluctuation of memory but ...

[CrashReport] UE4Editor_Engine!FBlueprintDebugData::FindBreakpointInjectionSites() [blueprintgeneratedclass.h:382]

UE - Gameplay - Blueprint - Aug 29, 2017

This is a common and longstanding crash that has occurred since at least 4.9 and affected over 280 users. User DescriptionsI added an item to a BP struct. Last time I did this (several months ago) ...

Calling a Multicast RPC from a Player Controller creates a new Player Controller on the Client

UE - Networking - Jun 3, 2015

Calling a Multicast RPC from a Player Controller creates a new Player Controller on the Client. In 4.7.6, this results in a repeating log warning: "LogPlayerController:Warning: Calling IsLocalContro ...

BuildCookRun: EnablePlugins parameter generated improper cooking command line.

From the UDN post that reported the problem:  The BuildCookRun Automation script offers a commandline option called -EnablePlugins= which allows the user to specify additional plugins that should ...

Oculus Quest - Loading splash no longer shown

UE - Platform - XR - Nov 12, 2019

Oculus Splash screen image no longer shows on Quest. Unable to reproduce on PC (If you package a project without 'Start in VR' enabled you will be able to see splash until you enable HMD) Conf ...

ULevelInstanceSubsystem::CreateLevelInstanceFrom() is not honoring parameters bAlwaysShowDialog and LevelPackageName

UE - World Creation - Worldbuilding Tools - Level Instances - Aug 6, 2025

A Level Instance or Packed Level Actor can be created through editor scripting by using function ULevelInstanceSubsystem::CreateLevelInstanceFrom(), which receives parameters packed in the FNewLevel ...

LevelSequenceActorSpawner::GetLevelStreaming() fails to compare sub level names when running in Pie

UE - Anim - Sequencer - Sep 26, 2019

The problem is in the function with signature "ULevelStreaming* GetLevelStreaming(FString SafeLevelName, UWorld& World)" within LevelSequenceActorSpawner.cpp at line 30. The problem is with the Safe ...

In-editor hitch when deleting one actor in a world with many loaded actors

UE - CoreTech - Nov 17, 2023

When editing a level with many actors (1000+), deleting an actor results in a noticeable hitch: the editor becomes unresponsive for seconds. This hitch becomes longer the more actors are loaded and ...

Ensure thrown when applying a Linear Color User Exposed Variable in a Niagara Emitter

UE - Niagara - May 20, 2022

This is a regression tested in //UE4/Release-4.27 CL18319896. Ensure thrown when applying a Linear Color User Exposed Variable in a Niagara Emitter. ...