Niagara Oscilloscope hangs indefinitely in cooked build

UE - Audio - Dec 9, 2020

Cooked games will hang on startup when using the Oscilloscope data interface due to an indefinite wait in FNiagaraSubmixListener::UnregisterFromSubmix  When setting GCVarEnableAudioCommandLogging t ...

BP - Nativization will fail at cook time if a BP class and a User-Defined Structure reference each other.

UE - Gameplay - Blueprint - Apr 20, 2017

Note: This happens with "Exclusive" nativization mode as well. This occurs because the nativized UDS 'GetDefaultValue()' method is generated into a .h file rather than a .cpp file. This creates a c ...

Localization manifest writing fails if source control is hooked up and the manifest file does not exist already.

UE - Editor - UI Systems - Localization - Jun 16, 2015

First one happens on a clear project without any localization settings ever made. Gather Text commandlet log has theese lines in it: [2015.06.16-13.21.56:396][ 0]LogInit:Display: SourceControl:Err ...

Using xcode-select to switch between Xcode 10 and Xcode 11 beta can cause Xcode 11 to be unrecognized by the editor

UE - Platform - Apple - Jul 16, 2019

After switching from Xcode 11.0 Beta 3 (11M362v) to Xcode 10 (10A255) and then back to Xcode 11, the editor no longer recognized that Xcode was installed on my machine when trying to use Xcode 11 as ...

When painting on a landscape with edit layers, there are UV distortions happening across the boundaries of paint layers when material is using SetMaterialAttributes

UE - Graphics Tools - Terrain - Landscape - Mar 10, 2025

Context Landscape Edit Layers enables users to paint landscapes using non-destructive layers, and can add multiple layers to the landscape that can be edited independently from each other. Problem ...

Assertion failed after closing project on Oculus Mobile - Referencing AudioMixerSourceManager.cpp:300

UE - Audio - Apr 30, 2019

This assertion seems to occur when closing the project while a sound is playing on the device. Assertion failed: CommandBuffers[NextIndex].SourceCommandQueue.Num() == 0 [File:D:/P4Workspaces/Switch ...

[CrashReport] UE4Editor_UnrealEd!UnFbx::FFbxImporter::RecursiveBuildSkeleton()

UE - Editor - Content Pipeline - Import and Export - Jul 30, 2015

This is a common crash affecting users. User DescriptionsJust import a Mesh of Fuse Source Context 624 void UnFbx::FFbxImporter::RecursiveBuildSkeleton(FbxNode* Link, TArray<FbxNode*>& Out ...

[CrashReport] Crash on Mac - UE4Editor-SlateCore.dylib!SWindow::IsVisible()

UE - Platform - Apple - Jun 23, 2017

This is a common crash on Mac in the 4.16 release, and has occurred with low frequency since at least 4.11. Users have not provided any descriptions, so additional information is currently unknown. ...

ApplicationReceivedScreenOrientationChangedNotificationDelegate does NOT work properly on Android

UE - Platform - Mobile - Aug 5, 2019

ApplicationReceivedScreenOrientationChangedNotificationDelegate supports iOS but not Android. Probably, Java_com_epicgames_ue4_GameActivity_nativeOnConfigurationChanged should be useful for fix thi ...

Morph target is not applied on the first frame in Level Sequence

UE - Anim - Rigging - Dec 4, 2025

When a skeletal mesh with morph targets spawns in the sequence, the morph is not reflected in the first frame.  In the ProcessStage_SkinCache call of SkeletalMesh, MorphVertexBuffer->SectionIds is ...