Unreal Engine Issues
Unreal Engine Issues
Crash on adding new element to ChaosCacheCollection if ChaosCacheCollection is open in editor
UE - Simulation - Physics - Destruction - Dec 11, 2020More ways to reproduce:In Chaos Cache Collection Editor press Add Element button (no matter when you will do this step)If in Step13 from Steps to reproduce you won't place Chaos Cache Collection Edi ...
Client crashes after second seamless travel when a blueprint manually placed in the world spawns a replicated actor
UE - Networking - Sep 19, 2019When a user loads into a level that spawns replicated actors using manually placed blueprints twice using ServerTravel with Seamless Travel enabled it will crash. It looks like the engine can't find ...
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 ...
Typo in "BaseEditorSettings.ini": under section [/Script/UnrealEd.ContentBrowserSettings], key "DisplayPluginFolder" (singular) should read "DisplayPluginFolders" (plural).
UE - Foundation - Oct 11, 2025File "<ENGINE_PATH>/Engine/Config/BaseEditorSettings.ini" contains the following setting: [/Script/UnrealEd.ContentBrowserSettings] ; Whether to display the game project plugins in the Content Brow ...
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 ...