Assertion failed in FAudioDevice::UnregisterSoundClass when GC

UE - Audio - Aug 13, 2018

The licensee reported that check(IsInAudioThread()) was failed in FAudioDevice::UnregisterSoundClass when GC. The following is the call stack: 1 #00 pc 030d7b58 libUE4.so HandleError (/home/pirates ...

Auto-Save failing, pulling old saves and blocks users from continuing

UE - Editor - Workflow Systems - May 15, 2023

Reporting an issue where are users are getting prompted to auto-save, but then it appears to fail and asks them to manually save. They're being prompted with outdated save files, but get stuck in a ...

Crash caused by a race condition in Nanite::DispatchBasePass()

UE - Rendering - Graphics Features - Nanite - Feb 25, 2026

Nanite::BuildShadingCommands() launches two asynchronous tasks: ShadingCommands.SetupTask ShadingCommands.BuildCommandsTask BuildCommandsTask is responsible for modifying ShadingCommands.Commands ...

[CrashReport] Linux crash - FVulkanDynamicRHI::Init()

UE - Platform - Linux - Aug 16, 2017

This is a trending Linux crash in 4.17.0 that has also occurred in 4.16 Callstack from LogLogLinux: Error: appError called: Assertion failed: Assertion failed: [File:/home/---/UnrealEngine/Engine/ ...

Nativized packaging fails when attaching paper Flipbook component to a parent paper Flipbook component that is Inherited.

UE - Gameplay - Blueprint - Jan 8, 2019

Nativized packaging fails when attaching paper Flipbook component to a parent paper Flipbook component that is Inherited. ...

[CrashReport] UE4Editor_Engine!USceneComponent::UpdateComponentToWorldWithParent() [scenecomponent.cpp:492]

UE - Gameplay - Components - Aug 29, 2017

This is a common and longstanding crash that has occurred since at least 4.12 and affected more than 400 users. User DescriptionsWas following the first Blueprint tutorial and dragged the geometry ...

FPackedRGBA16N is divide by 32768 twice in NEON/FPU

UE - Platform - Mobile - May 6, 2022

Certain UPROPERTY values are not updated during auto-recompile

UE - Gameplay - Blueprint - Aug 4, 2016

Sometimes manual recompile is required to make a blueprint actually recompile data-only changes, but not always. If the last manual compile was with default values, then changes are not updated. If ...

After upgrading a project from 4.7 to 4.8 and compiling a blueprint that casts to and pulls a variable from a widget will cause a freeze if the widget is then compiled

UE - Gameplay - Blueprint - May 7, 2015

If the user has a project that casts to a widget to pull out a variable in a 4.7 project. This can cause a freeze after upgrading the project to 4.8 preview. This happens when the user compile the b ...

[CrashReport] UE4Editor-TargetDeviceServices.dylib!TRawMessageHandler<FTargetDeviceServicePong, FTargetDeviceProxyManager>::HandleMessage(TSharedRef<IMessageContext,()

UE - Platform - Apple - Oct 5, 2017

This is a slightly common Mac crash that has occurred since 4.17.1. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log[2017.09.28-15.29.17:473][3 ...