Unreal Engine Issues
Unreal Engine Issues
Editor crashes when changing skeletal mesh if another skeletal mesh component is attached when using master pose node
OLD - Anim - Jan 27, 2020The crash only occurs if the additional skeletal mesh component is used with Set Master Pose Component (see ToggleAttach function in the TopDownCharacter BP). It doesn't seem to matter what mesh we' ...
Set user focus for player 0 will cause other local players to lose input
UE - Gameplay - Input - Feb 28, 2019When the player at index 0 sets its user focus it will cause other players to lose input. This does not occur when setting the user focus of players with an index higher than 0. ...
World Source in Take Recorder does not record auto-tracked actors properly
UE - Virtual Production - Tools - Take Recorder - May 23, 2025The Take Recorder plugin allows for multiple sources to be recorded during gameplay. The World Source is expected to record everything in the level when the Autotrack Actors option is enabled. Once ...
Crash after adding Virtual Bone, then Creating Asset
OLD - Anim - Jul 5, 2017Occurs on? 4.16 - 3466753 - YES 4.17 - 3521650 - YES Error message: Assertion failed: RefBonePose.Num() == NumBones [Link Removed] [Line: 4400] Source Context:4387 ResetAnimation(); 4388 ...
Exception generated launching Horde Agent built with 5.6
UE - Foundation - Horde - Server - Jul 28, 2025The source of the problem seems to be using IOptionsSnapshot with a Singleton. Per the MS documentation for IOptionsSnapshot, "Is registered as Scoped and therefore can't be injected into a Singleto ...
Race condition in full builds of UE4 engine source
UE - Foundation - Cpp Tools - UnrealBuildTool - Sep 26, 2019This is a race condition caused by how "Clean.bat", a batch file used during rebuilds, tries to manually rebuild the UnrealBuildTool project when it runs. This causes a spam of UnrealBuildTool build ...
PATH not passed to NMake script when building Android from Visual Studio
UE - Foundation - Cpp Tools - UnrealBuildTool - Jan 25, 2023After upgrading from UE5.0.3 to UE5.1, we started seeing this error when trying to build Android Development from Visual Studio (VS2022 17.2.1): Running UnrealBuildTool: dotnet "..\..\Engine\Binari ...
Illegal reference to private object when cooking a child level sequence with a time warp track
UE - Anim - Sequencer - Apr 28, 2025Slack: [Link Removed] Cook error: UATHelper: Cooking (Windows): LogSavePackage: Warning: UATHelper: Cooking (Windows): Referencers of MovieSceneTimeWarpSection /Game/ChildSequence.ChildSequence: ...
Crash when upgrading Nvidia GFX driver from Version 457.85 with open Project
UE - Graphics Features - Nov 18, 2022Repro Rate: 5/5 Summary: When opening a Project in UE version 5.1.0 with Nvidia GFX driver version ###, the user is notified that there are known issues with this driver through a pop-up:WARNING: K ...
Crash on attempt to clear(NullifyInstance) of duplicated Hierachial Instanced Static Mesh
Tools - May 31, 2019When creating an C++ Actor with a Hierarchical Instanced Static mesh. when duplicating such an actor with mesh instances, the instances are not visible on the level. In this state, calling HISM comp ...