Unreal Engine Issues
Unreal Engine Issues
FileSystemDerivedDataBackend may output a corrupted access log
UE - Foundation - Core - Derived Data - May 20, 2021This problem is caused by the AccessLogWriter has not been flushed at the termination. The following workaround flushes the Writer.class FFileSystemDerivedDataBackend : public FDerivedDataBackendInt ...
The 'Set Constrained Components' node doesn't set the physics constraint components correctly if used in the Construction Script
UE - Simulation - Physics - Jan 20, 2015The 'Set Constrained Components' node doesn't set the physics constraint components correctly if used in the Construction Script. ...
The Sorting Issue Between Height Fog and Transparent Objects
UE - Graphics Features - Aug 21, 2024When a LocalFogVolume is used with ExponentialHeightFog, it does not correctly fog translucent objects. ExponentialHeightFog and Volumetric Fog from a LocalFogVolume both correctly occlude transluc ...
Crash when calling SetState inside state machine OnUpdate
UE - Anim - Sep 5, 2025The crash happens when SetState is called inside the function bound to OutputAnimationPose’s OnUpdate in the animation state. This way of using Set State node is the same as shown in the official do ...
Widget "Listen For Input Action" executes on unexpected input event
UE - Editor - UI Systems - Feb 19, 2020Listen For Input Action firing erroneously. Confirmed in 4.26 MAIN @ CL 11536993 ...
Destructible attached with a Physics Constraint have inconsistent physics
UE - Simulation - Physics - Destruction - Jul 26, 2016Destructible attached with a Physics Constraint have inconsistent physics compared to a standard Static Mesh. This is also sometimes prevalent with Destructibles that aren't attached with a Physics ...
Incorrect derivative ops detection when Add node is used with Nanite Pass Switch node in material graph
UE - Graphics Features - Mar 11, 2025Plugging an Add node which adds a constant value into a Nanite Pass switch node results in derivative ops to be detected where there should be none (which show up as red in the No Derivative Ops deb ...
Crash, Couldn t find Shader FHitProxyVS for Material Resource M_Glass
UE - Graphics Features - Aug 18, 2014Changing the properties of M_Glass and M_Metal_Copper to two sided via the property matrix crashes the editor to desktop. (Note: M_Glass with ANY of the M_Metal Materials except M_Metal_Chrome will ...
Crash when using StaticDuplicateObject with mismathced Source and Destination class types
UE - Foundation - Jun 19, 2025Starting in Unreal Engine 5.4, StaticDuplicateObject internally switched to using Unversioned Property Serialization (UPS) for performance reasons. However, UPS assumes the source and destination ob ...
Crash when Undo after deleting a Material Layer of a Material Instance.
UE - Rendering Architecture - Materials - Apr 2, 2025In Unreal Engine version 5.5.4, the Editor crashes when performing Undo after deleting a Material Layer of a Material Instance ...