Unreal Engine Issues
Unreal Engine Issues
Editor Crashes when importing some FBXs with multiple Material IDs in 4.14.2
UE - Editor - Content Pipeline - Import and Export - Jan 5, 2017This is a regression in behavior between 4.14.1 and 4.14.2! The editor will crash when importing FBX meshes that have multiple material ID assignments. If it's a single material ID it will import w ...
Crash editing Landscape Splines with Level Sequence Open
Tools - Mar 6, 2017A crash occurs when attempting to transform a landscape spline with a Level sequence open. It is important to note that no key framing or animating of the landscape spline control point is occurrin ...
Crashes after destroying a skeletal mesh attached via socket name (not bone name), the destroyed mesh remains welded.
UE - Simulation - Physics - Jul 18, 2025On welding physics bodies during primitive component attachment, UPrimitiveComponent::WeldToImplementation() calls GetRootWelded() and then GetBodyInstance() on the returned root. This searches by b ...
Crash opening FaceARSample on iOS
UE - Platform - XR - Jul 26, 2019FaceARSample is crashing as soon as it is opened on iOS. Tested on a iPhoneXS 12.4. Regression: Yes I was able to get FaceARSample on the same device the previous release 4.22. ...
Material Graph Editor crash when changing the value of a node entering a reentrant expression
UE - Rendering Architecture - Materials - Oct 1, 2024It is possible to cause an editor crash when changing a the value of a node involved with a reentrant expression. See the steps to reproduce for more information. Specifically, the crash occurs whe ...
Crash Occurs When Mesh is Reimported Multiple Times in the Mesh Editor
UE - World Creation - Worldbuilding Tools - Foliage - Jan 24, 2018Engine crashes when asset has been reimported multiple times through the mesh editor -Editor crashes in Main when reimporting -Editor crashes in 4.17 when changing the Import Transforms ...
Niagara Fluids Grid3D_Gas_Explosion causes a crash
UE - Niagara - May 4, 2022Placing Grid3D_Gas_Explosion into a level then packaging the level for windows will crash the packaged project. The package will give an error that it crashed while loading and quit. This does not ...
FAnimationRuntime::BlendPosesPerBoneFilter() causes an assertive crash when Skeletal Mesh LOD is changed
UE - Anim - Runtime - Nov 1, 2023The crash occurs from "check(BoneBlendWeights.Num() == NumBones);" This crash occurs when the following conditions are met;The skeletal mesh LOD is changed.The number of bones is difference between ...
Crash when changing window resolution with AMD GPU, D3D11 and renderoffscreen
UE - Rendering Architecture - RHI - Apr 9, 2025Context A crash can be induced with running Unreal Engine with DirectX11, a AMD GPU and running -renderoffscreen flag, and the main window is resized. This issue was first observed with the PixelStre ...
Using Deferred Decal Material With Dbuffer Decal Enabled Crashes Editor
UE - Graphics Features - Nov 16, 2016When using a deferred decal material (while Dbuffer Decals are enabled) on an asset and then going fullscreen in the viewport will cause the engine to crash. Note engine doesn't crash when material ...