LoadErrors:Warning: Warning CreateExport: Failed to load Outer for resource when moving Blueprints folder to another folder

UE - Gameplay - Blueprint - Apr 14, 2017

There are 3 assets from Content > Blueprints > Missing Types that are failing to be moved over The assets are causing the warnings are:BP_NodeClassIsMissingBP_ParentClassIsMissingTypeBP_PinReferenc ...

Actors disappearing after saving a large number of modifications to world partition maps

UE - Editor - Nov 4, 2022

From Licensee: "We've encountered a world partition bug where newly created actors go missing in the viewport and Outliner after saving modifications to a large number of actors. This bug is partic ...

[CrashReport] UE4Editor-Engine.dylib!bool FHighResScreenshotConfig::SaveImage<FLinearColor>()

UE - Graphics Features - Jul 27, 2017

This is a common crash occurring on Mac in 4.15 and 4.16. Users have not provided any additional descriptions. Callstack from LogAssertion failed: Assertion failed: Bitmap.Num() == x * y [File:/Use ...

Half precision is not supported for OpenGL ES 3.1 Pixel Shaders

UE - Platform - Mobile - Apr 6, 2018

Fix the cross compiler so half precision is supportedAdd a project setting to specify the default precision to support on ES31. Be sure the shader version takes this setting into account. — User des ...

Crash when editing Gameplay Effect containing a deleted/renamed Gameplay Attribute

UE - Gameplay - Gameplay Ability System - Mar 9, 2025

When modifying the name of a gameplay attribute that is used with a modifier on a gameplay effect, attempting to remove/change the modifier causes an editor crash. This appears to be due to line 29 ...

LevelStreamingPersistence: BP added components don't persist properties in PIE until map actor resave

UE - World Creation - Worldbuilding Tools - Mar 6, 2026

Context The LevelStreamingPersistence plugin can be used to remember and restore properties on actors, components and other objects that are part of a streamed level. Persisted properties are resto ...

This Blueprint will not compile and causes a crash in 4.8

UE - Simulation - Physics - Mar 18, 2015

The MiningBuilding Blueprint in this user's project will not compile. Clicking the compile button never switches it to "Good to Go", and a warning that it needs to be compiled appears at PIE. Repro ...

LayeredBlendPerBone without BlendRootMotionBasedOnRootBone exaggerates root motion

UE - Anim - Runtime - May 27, 2023

When BlendRootMotionBasedOnRootBone is false, the LayeredBlendPerBone is aggregating root motion of the child poses ontop of the base pose root motion.  (ie. if the first child pose's blend weight i ...

Niagara Mesh Renderer registers NumParticles x NumMeshVariants TLAS instances

UE - Rendering - Graphics Features - Ray Tracing - May 28, 2026

When using the Niagara Mesh Renderer with multiple mesh variants selected via MeshIndex, the number of TLAS instances allocated is NumParticles × NumMeshVariants and enabling the Path Tracer can ca ...

Client Gameplay Effect stuck on due to duplicate ReplicationIDs

UE - Gameplay - Gameplay Ability System - Oct 31, 2025

We've been tracking down a problem recently with the Gameplay Ability System where a gameplay effect is properly removed on the server, but the client has the gameplay effect stuck on permanently. ...