Spawned skeletal animations don't animate

UE - Anim - Sequencer - Oct 30, 2017

Server crashes when client connects after Server has reloaded a sublevel with a deleted actor

UE - Networking - Jul 13, 2017

UNetDriver::DestroyedStartupOrDormantActors maintains a list of deleted startup (and dormant) actors. This is used to notify clients that have joined the server of Actors that need to be destroyed ...

Out-of-Bounds Access During Partial Updates of ISMC Per-Instance Custom Data

UE - Rendering - Features - Jan 6, 2026

When using instance custom data values, removing an instance and changing the number of custom data floats in sequence can cause an array-out-of-bounds crash. The underlying arrays are not resized ...

Sequential Level Loading in Python causes Crash

UE - Editor - Workflow Systems - Apr 16, 2019

Loading all the levels selected in the Content Browser and running the aforementioned Python script causes the editor to crash Tested in 4.20.3 (CL - 4369336), 4.21.2 (CL - 4753647), 4.22 (CL - 5 ...

LIVE: Code projects using TextureRenderTarget2D will not build because UTextureRenderTarget is undefined in TextureRenderTarget2D

UE - Foundation - Core - Nov 5, 2014

If a TextureRenderTarget2D is used in a code class, the build of the project will fail with an error stating that the UTextureRenderTarget base class is undefined. The line #include "Engine/TextureR ...

Client crash on seamless travel in DataReplication with lag

UE - Networking - Jan 11, 2016

When server traveling, client may crash due to lag while attempting to replicate object/property. ...

Assertion failed: PlatformNeedsExtraDeletionLatency()

UE - Rendering - Architecture - RHI - Mar 5, 2019

Animating a HISM along a spline when many other HISMs are present will result in a crash in 4.22. Confirmed in 4.23 MAIN @ CL 5291468 ...

Making changes to a Camera Shake while previewing the Camera Shake triggers a crash

zComponent - Archive - May 23, 2022

This is not a regression. Tested in //UE4/Release-4.27 CL 18319896  Making changes to a Camera Shake while previewing the Camera Shake triggers an Assertion upon compiling. ...

Crash when deleting the Add Component By Class node after changing the Relative Transform of the component

UE - Gameplay - Blueprint - Mar 31, 2021

When adding the Add Component By Class node, choosing a class that has a Relative Transform pin, changing the transform, and deleting the node the editor crashes. I tested this with the Skeletal Mes ...

Deleting elements from TMap Struct in actor blueprint editor causes Crash

UE - Editor - UI Systems - Slate - May 24, 2019

Deleting elements from TMap Struct in the Actor Blueprint Editor (specifically, deleting elements from them) causes Unreal to crash ...