Unreal Engine Issues
Unreal Engine Issues
Replacing Selected Actors does not replace all references.
Tools - Oct 21, 2015When using the "Replace Selected Actors with" feature in the editor, references to the replaced actor are not updated to reference the new actor (where valid). They will appear to be replaced until ...
Physics Constraints have unexpected behavior when used on nested static mesh components
UE - Simulation - Physics - Jul 5, 2017Physics Constraints have unexpected behavior when used on nested static mesh components. Simulating inside of the blueprint has a similar effect to what is expected but when the BP is added to the l ...
[CrashReport] FUniformExpressionSet::CreateUniformBuffer() materialuniformexpressions.cpp
UE - Graphics Features - Jul 14, 2017This is a common crash occurring for users in 4.16 User Descriptionsdeleting a texturecrash occurred when reverting two textures Source Context 266 /** 267 * @returntrueifthis ob ...
Interpolators of Particle Dynamic Parameters Need "nointerpolation".
UE - Niagara - Aug 1, 2019Regardless Niagara or Cascade, dynamic parameters for particles are passed to pixel shaders from vertex shaders via InterpolantsVSToPS. It can cause a precision error on some materials, for example ...
FBX reimport issue with Interchange Framework
UE - Editor - Content Pipeline - Import and Export - Sep 15, 2025A licensee has reported that the following repro steps can result in a "Failed to merge bones" error:One of our Skeletal Mesh assets was imported into engine version 5.4 using an older version of th ...
Multi Sphere Trace is not returning the correct Impact Location
UE - Simulation - Physics - Jan 19, 2015Multi Sphere Trace is not returning the correct Impact Location. Other AnswerHub Report:https://answers.unrealengine.com/questions/30952/multisphere-trace-fhitresult-location-same-as-impa.html ...
[CrashReport] UE4Editor_HotReload!`FHotReloadClassReinstancer::UpdateDefaultProperties'::`2'::FPropertyValueMemoryWriter::operator<<() [hotreloadclassreinstancer.cpp:372]
UE - Foundation - Core - UObject - Sep 14, 2017This is a common crash that has occurred for users since at least 4.16. User DescriptionsUsing the PIE i compiled some c++ then quit the PIE before the end of the compilation. Source Context 35 ...
Error on Loading Pawn Blueprint Containing ActorSequenceComponent from GameMode Constructor
UE - Anim - Sequencer - Oct 25, 2017When attempting to load a Blueprint that contains a ActorSequence component from inside of a Gamemode's constructor, errors are given. The ActorSequence component is also removed from the Blueprint ...
Build Plugin process fails with null reference exception when building a plugin that has "Can Be Used With Unreal Header Tool" set to true
UE - Foundation - Cpp Tools - Dec 18, 2018Trying to use UAT to build a plugin that has CanBeUsedWithUnrealHeaderTool set to true will fail due to a null reference exception (log from Main CL 4666322 attached). This happens because the plugi ...
Adding an Object to a Plugin using the C++ Class Wizard results in a compilation error.
UE - Foundation - Core - Jan 10, 2019Adding an Object class to a plugin's module using the C++ Class Wizard results in a compilation error due to attempts to edit the new class' generated.h file during the initial compilation attempt. ...