Unreal Engine Issues
Unreal Engine Issues
World Partition - Deleted actors can become unloaded prior to saving
UE - World Creation - Worldbuilding Tools - World Partition - Apr 11, 2025In world partition levels, deleted actors can become unexpectedly unloaded prior to saving, causing loss of work. Specifically, this issue occurs after the undo history has been cleared (either manu ...
Incorrect Velocity Calculation at Animation Sequence Transitions in Level Sequence
UE - Anim - Sequencer - Feb 18, 2025When adding an Animation Track to a Level Sequence and placing Animation Sequences back-to-back without gaps, the velocity can be miscalculated at the transition between sequences. This issue occur ...
[CrashReport] Assertion failed: !bRequireNormalization - UE4Editor_Landscape!ULandscapeComponent::ReplaceLayer()
UE - LD & Modeling - Terrain - Landscape - Jul 19, 2017This is a common crash affecting users in 4.16, and has occurred since at least 4.14. Over 200 unique users have been affected, though they have provided little information. User DescriptionsI am a ...
Unfocused Standalone window has reduced performance
UE - Rendering Architecture - RHI - Aug 25, 2020User description: When I run two windowed standalone instances to test multiplayer, the unfocused window gets about 2-5 fps...but if I focus on it, smooth 120fps, yet the opposite screen is now onl ...
Crash when quick binding a function in a class that extends LevelSequenceDirector
UE - Anim - Sequencer - Sep 16, 2020The purpose was to create a Level Sequence Director inheritance class so that the same event could be reused in multiple sequencers. Attempting to quick-bind this base Level Sequence Director event ...
[CrashReport] UE4Editor_CoreUObject!FLinkerSave::FLinkerSave() [linkersave.cpp:31]
UE - Foundation - Core - Aug 22, 2017This is a longstanding and common crash that has occurred since at least the 4.11 release. The error appears to occur while trying to access a .tmp file. User DescriptionsI left unreal unattended ...
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 ...
[CrashReport] UEdGraphSchema_K2::PinHasSplittableStructType
UE - Gameplay - Blueprint - Sep 14, 2017This crash is affecting a few users in 4.17. ...
Niagara Emitter editor forgets Timeline playback ranges
UE - Niagara - Sep 14, 2020This seems to only affect an emitter and not a system asset. ...
PlayerController::PlayDynamicForceFeedback called through code does not fire
UE - Gameplay - Input - Feb 25, 2016Calling PlayDynamicForceFeedback in code does not affect controller rumble. ...