Packaging Error When Setting Recast Nav Mesh Runtime Generation

UE - AI - Jan 25, 2016

Setting the Runtime Generation on the Recast Nav Mesh to a different preset than what is set in the Project Settings causes an error to appear upon trying to package the project, and causes the pack ...

Changes to Instanced Properties default value on BP not propagated to placed actors in the opened level

UE - Foundation - May 15, 2025

In UE versions 5.4 and onwards (as of CL 42589677 in Main), when an Instanced UObject property is defined in an Actor Blueprint, modifying the default value in the Blueprint does not propagate the c ...

[CrashReport] UE4Editor_CoreUObject!FPackageName::LongPackageNameToFilename() [packagename.cpp:381]

Tools - Jul 14, 2017

This is a common crash affecting users in 4.15 and 4.16. It appears to often occur while editing static meshes. User DescriptionsI was editing a mesh, added a socket, didnt immediately rename it, s ...

[CRASH]SIGSEGV: invalid attempt to access memory at address 0x0

Tools - Jan 7, 2015

Callstack: <CALLSTACK START> FTaskThread::ProcessTasksUntilQuit(int) Address = 0x1091943e5 (filename not found) [in UE4Editor-Core.dylib] RenderingThreadMain(FEvent*) Address = 0x10de37e4b (filena ...

Editor Crash When DFAO Viewport Has Zero Area

UE - Graphics Features - Apr 19, 2018

I've reproduced this crash in 4.16, 4.17, 4.18, 4.19, and Main. Per licensee: The editor crashes if distance field ambient occlusion is enabled and a viewport is resized to have zero height. Th ...

[CrashReport] FGenericPlatformMemory::OnOutOfMemory | TArray<FCompressedChunk,FDefaultAllocator>::ResizeTo

UE - Foundation - Core - Jul 20, 2017

This is a common crash affecting users in 4.16, and has occurred since at least 4.12 for more than 200 unique users. The callstack has similarities to [Link Removed], and as-such may be out of our ...

A Client connected to a Server that then destroys the session and rejoins will be disconnected after a short time

UE - Networking - Dec 8, 2015

A Client connected to a Server that then destroys the session and rejoins will be disconnected after a short time. Unable to reproduce in a new project, however this has been reported multiple times ...

Foliage lightmaps for LODs does not look correct

UE - World Creation - Worldbuilding Tools - Foliage - Jun 21, 2016

When using the foliage tool with any mesh that has a LOD the lightmap generates artifacts for the instance. The base LOD will have correct looking lightmaps, however when pulling back and seeing the ...

[CrashReport] Fatal error: Cast of nullptr to Object failed

UE - Gameplay - Oct 5, 2017

This is a common and longstanding crash that has affected many users since at least 4.11. Source context not available (error in user code?). User DescriptionsI was duplicating a Set function in c ...

Crash when hiding DataTable window and saving in DataTable Editor

Tools - Nov 20, 2017

When adding rows to a DataTable that has its DataTable tab hidden or exited out, the Editor will crash when adding a row to the DataTable. This crash happens in 4.17, 4.18, and 4.19. ...