Ensure occurs when RBAN simulated rigid body approaches UseComplexAsSimple mesh

UE - Simulation - Physics - Character - Jun 30, 2022

When a collision enabled RBAN node attempts to collect surrounding meshes, if there is a mesh with UseComplexAsSimple, it will hit the Ensure when cloning a mesh on the task graph thread. Disabling ...

Editor can crash while performing a Hot Reload after a custom UClass class is added to the project

UE - Foundation - Cpp Tools - Hot Reload - Mar 14, 2019

Performing a Hot Reload after creating a custom UClass class can result in a crash. This was reported on Linux, but reproduced on Windows. Additional testing will be done on Linux to confirm the is ...

Using ConstructorHelpers::FClassFinder in a GameMode constructor may result in a default value or crash if the level is reloaded multiple times.

UE - Gameplay - Oct 27, 2015

Randomly selecting a character class from the GameMode constructor using ConstructorHelpers::FClassFinder can result in default or null character being set when the level is reloaded. It appears tha ...

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 ...

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 ...

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. ...

Virtual Bone caused nanite skinned mesh crash

UE - Graphics Features - Nanite - May 31, 2025

When a Nanite skeletal mesh has a virtual bone the engine can crash when changing LODs ...

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 ...

After Seamless Server Travel, the Client cannot move the character or see the Server character

UE - Networking - Jul 9, 2015

After Seamless Server Travel, the Client cannot move the character or see the Server character. On the Server, the Client character appears to be falling in place. Tested in both first and third per ...

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

UE - Anim - Sequencer - 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. ...