Blueprint's location reset to 0, 0, 0 after being detached in a network environment

UE - Networking - Apr 24, 2017

Attaching / Detaching a blueprint actor to a player in a network environment causes location errors when the detach occurs. Even without the attach events being replicated or the blueprint's movemen ...

Phaser module is malfunctioning

UE - Audio - Apr 9, 2019

The phaser module that is part of the new Audio Engine causes audio from a Sound Cue to mute after playing for one second. The user states that the issue comes from the Phaser.cpp file producing a N ...

Python crash the engine at exit.

UE - Editor - Workflow Systems - Oct 25, 2022

A UDN reported various crashes at exit in the embedded Python library. I was able to repro the issue in Release-5.1 and trace it back at the point where python runs its garbage collection in Py_Fina ...

Crash in AWorldDataLayers::InitializeDataLayerRuntimeStates() when quickly unloading then loading a sub-world partition

UE - World Creation - Worldbuilding Tools - Data Layers - Mar 6, 2025

From licensee: Since we integrated 5.5, we are experiencing a crash in AWorldDataLayers::InitializeDataLayerRuntimeStates() on this line check(ActiveDataLayerNames.IsEmpty() && LoadedDataLayerN ...

Custom Depth range is different than Pixel Depth range

UE - Graphics Features - Sep 25, 2025

Shaders that compare custom depth and pixel depth get wrong output values because the ranges are different. This error is most noticeable over large distances. The difference in ranges is due to t ...

When r.SSR.Stencil is enabled, there is wrong logic observed.

UE - Graphics Features - Dec 19, 2025

When r.SSR.Stencil is enabled, the areas with high roughnesss are not discarded and Unlit materials are incorrectly handled. See the linked EPS case (Additional Info URL) for a full explanation of ...

[CrashReport] UE4Editor-MetalRHI.dylib!FMetalDeviceContext::CreateDeviceContext()

UE - Graphics Features - Feb 10, 2017

Error message: SEGV_MAPERR at 0x3 Source Context: Most recent user affected CL: 3249277 Logs: [Link Removed] [Link Removed] [Link Removed] [Link Removed] CrashReporter User Descriptions:Just i ...

[CrashReport] Assertion failed: Canary == ShaderMagic_Initialized

UE - Graphics Features - Jun 13, 2017

This is a common crash among the community since at least the 4.14 release. Additional information is not currently available. This is spread among numerous different CrashGroups between releases w ...

Physics Substepping doesn't have the same effect from 4.15 to 4.16

OLD - Anim - Aug 8, 2017

Physics Substepping doesn't have the same effect from 4.15 to 4.16. In 4.16+ the ponytail in the provided project will have a jitter effect even with substepping enabled. This is a regression: Work ...

[CrashReport] UE4Editor_UMG!TBaseDelegate<FMargin>::operator=() [delegatesignatureimpl.inl:381]

UE - Editor - UI Systems - Aug 29, 2017

This is a longstanding and common UMG crash that has affected more than 200 users since at least the 4.15 release. User DescriptionsI was working in the UI and undid several last changes in quick s ...