Unreal Engine Issues
Unreal Engine Issues
Crash when removing and re-adding instances to an InstancedStaticMeshComponent with PerInstanceCustomData.
UE - World Creation - Worldbuilding Tools - Jan 22, 2026When using an InstancedStaticMeshComponent with PerInstanceCustomData, the number of float elements in the "Custom Data" array should always be equal to NumCustomDataFloats multiplied by the number ...
[CrashReport] UE4Editor_Landscape!ALandscapeProxy::PostEditChangeProperty() [landscapeedit.cpp:3692]
UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017This is a common crash affecting users in 4.16. Unfortunately they have not provided any additional details. Source Context 3684 // Remove null layer infos 3685 EditorLayerSettings ...
[CrashReport] FGenericPlatformMemory::OnOutOfMemory | TArray<FCompressedChunk,FDefaultAllocator>::ResizeTo
UE - Foundation - Core - Jul 20, 2017This 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 ...
[CrashReport] UE4Editor_Slate!FSlateApplication::DrawWindowAndChildren() [slateapplication.cpp:1213]
UE - Editor - UI Systems - Slate - Nov 10, 2017This is a longstanding crash that has occurred since at least 4.13. User DescriptionsI cant package. Every time I try, I get a crash and an "Unknown Error"failed to switch between game modes and af ...
UConsole HistoryBuffer no longer writing to disk in packaged builds
UE - Core - Systems - Sep 7, 2023We started running into issues with the console history not saving after upgrading to 5.2.1. The console history (as in the commands last input into the in-game console) is no longer being saved bet ...
High Virtual Texture Sample/Lookup Cost when using a Virtual Texture in a Material Layer Blend
UE - Rendering - Architecture - Materials - Mar 14, 2025Some Material Attribute blends in Material Layer Blends can cause Virtual Texture samples to be duplicated in HLSL. This can be avoided by sampling the Virtual Texture in the Parent Material, and pa ...
Lightmass GI doesn't work with Material-based color changes
UE - Graphics Features - Sep 4, 2015A licensee is having trouble getting the visual results they want because Lightmass doesn't seem to handle color changes from materials. They are seeing this in 2 cases: (See attached images and tes ...
Particle record in the Matinee leads to crash when playing after record.
Tools - Oct 19, 2017Particle record feature in the matinee seems not properly working in the Editor. When trying to play in the matinee with recorded keys, the Engine will crash with Access violation - code c0000005. ...
Control Rig - Undo doesn't function correctly with proxy and multi bone controls
UE - ACT Character - Control Rig - Oct 26, 2025Issue from my Technical Animator where the undo operation in Control Rig doesn't work as expected on Proxy Controls. He has recreated the issue using the "Control Rig Samples Pack" and recorded a vi ...
UnrealCEFSubProcess requires Visual Studio 2013 to be compiled
UE - Foundation - Cpp Tools - UnrealBuildTool - Oct 21, 2016When trying to build the entire engine solution or UnrealCEFSubProcess directly, Visual Studio 2013 is required to be installed for UnrealCEFSubProcess to complete successfully. There is also an err ...