Crash when manipulating Bone Space IK before setting EffectorSpaceBoneName

UE - Anim - Rigging - Feb 9, 2017

Error message: Assertion failed: Pose.IsValidIndex(BoneIndex) [Link Removed] [Line: 528] Source Context: 513 const FTransform& ParentTransform = GetComponentSpaceTransform(ParentIndex); ...

Crash when building lighting while in PIE

UE - Graphics Features - Feb 21, 2017

NOTE: This issue is similar to (same callstack) as [Link Removed], however this issue is still occurring in 4.15.0. Error Message: Access violation - code c0000005 (first/second chance not availab ...

Translucent materials in the PostMotionBlur pass can cause a flickering viewport artefact when using TAA

UE - Graphics Features - Feb 5, 2025

There appears to be a bug relating to rendering multiple windows that can trigger under unknown circumstances. It has been reported on rectangle lights in the forums and on PostMotionBlur materials ...

Properties not serialized when moving actor/component depending on unrelated specifiers

UE - Framework - Blueprint - Sep 25, 2023

When an actor is moved on the level editor viewport, it is reconstructed along with its components, which at first makes their properties reset to their default state. Thankfully, this does not happ ...

Blueprints break when implementing a duplicated BP interface along with the original

UE - Framework - Blueprint - Mar 1, 2024

When duplicating a blueprint interface, the GraphGuids of the original BP interface's function graphs are unchanged: function graphs across the two BP interfaces now have the same GraphGuid. This is ...

When importing an FBX with Combine Meshes = False, one uasset will be created for the collection of assets.

Tools - Feb 4, 2016

When importing a mesh, there is an option to Combine Meshes, which by default is checked. Unchecking this option will bring in the individually named parts contained in the FBX as unique objects in ...

[CrashReport] Assertion failed: Array index out of bounds - GetPhysicsTriMeshData() [modelcomponent.cpp:688]

UE - Simulation - Physics - Oct 30, 2017

This is a semi-common crash that has occurred since at least 4.17.1. The callstack is nearly identical to [Link Removed], which was fixed in 4.18.0, however the error message and source context are ...

Users Unable to create C++ Projects

UE - Foundation - Core - Mar 6, 2015

2nd AH post with the same issue: https://answers.unrealengine.com/questions/183441/cant-load-c-projects.html Multiple people have reported not being able to create a C++ project. Creating a Bluepr ...

[CrashReport] UE4Editor_CoreUObject!FScriptArrayHelper::EmptyAndAddUninitializedValues() [unrealtype.h:2703]

UE - Gameplay - Blueprint Compiler - Aug 15, 2017

This is a trending crash coming out of the 4.17.0 release. Based on user descriptions, this crash occurs on Play or Compile for affected users. User DescriptionsAgain crashing when I hit playIF I C ...

[CrashReport] Mac crash - TArray<FDeferredMacEvent, FDefaultAllocator>::ResizeGrow

UE - Platform - Apple - Sep 14, 2017

This is a somewhat common crash on Mac that has affected users since 4.16. Users have not provided any descriptions of their actions when the crash occurred. Callstack from Log [2017.09.08-05.17. ...