Unreal Engine Issues
Unreal Engine Issues
Crash during Datasmith file import when not using Keep Hierarchy
TM - Interoperability - Jun 24, 2025Reported to support. The user has reported that one of their .udatasmith files will consistently crash in TM 2025.1.1 during import. This was consistently reproducible when importing using Collaps ...
Animated characters may appear in A pose after loading a file with Path Tracer enabled
TM - Rendering - Mar 12, 2025When saving a file with Path Tracer enabled at the time of save, animated characters will appear in an A pose state. This will persist until Path Tracer is disabled. Occurs in Twinmotion 2024.1.2 a ...
A warning is needed for turning off "Update Navigation Automatically", large nav meshes can cause crashes
UE - AI - Jul 7, 2015A warning is needed before allowing users to uncheck update Navigation Automatically. A user has done so and then created a nav mesh that was 1,000,000 by 1,000,000 in size and they can no longer op ...
Bug in ULevel::FixupActorFolders.
There is a potential bug in ULevel::FixupActorFolders() in the FixDuplicateFolders section: Suppose you have a folder hierarchy that looks like this:A B(1)B(2) C(1)B(3) C(2) where the letters ...
[CrashReport] UE4Editor_CoreUObject!UObjectBase::IsValidLowLevelFast() [uobjectbase.cpp:294]
UE - Foundation - Core - Aug 22, 2017This is a common crash in the 4.16 and 4.17 releases. User DescriptionsWriting a custom component in C++. Hotcompiled it through VS2017. Had the BP editor open with a class derived from that compo ...
If any light source is deleted, and a single light has its visibility state changed in LightMixer, all the other lights in the scene that were invisible turn visible
UE - Virtual Production - Tools - Jul 31, 2025If any light source is deleted, and a single light has its visibility state changed in LightMixer, all the other lights in the scene that were invisible turn visible. The behavior only shows after d ...
Plugins are not creating shipping versions on package on Mac 4.23 Preview
UE - Foundation - Cpp Tools - Jul 15, 2019When you try to package a plugin on Mac in 4.23.0 Preview 1 there is no Shipping folder generated. This was verified to not happen in 4.22.3 (via Epic Launcher). Found in 4.23.0 Preview 1 CL# 72363 ...
Traveling away from, then back to the original map in multi-process PIE with the editor as a client causes an assert
UE - Networking - Mar 28, 2016An assert is triggered in this case because in multi-process PIE, if the editor is a client, the PIEInstance of the world context remains at -1 (see UEditorEngine::PlayInEditor). If this client inst ...
sphere collision with start and end points set to the same value return no hit objects
UE - Gameplay - Aug 29, 2016Sphere collision with start and end points set to the same value return no hit objects. Workaround Set the end vector to 1 away from the start vector (0,0,0 to 1,1,1, etc.) Regression (no) issue ...
Source Textures used with a Rect Light are blurry and diffused
UE - Graphics Features - Mar 14, 2023This is a regression from 5.0.3 tested in the following streams:BranchChange ListResults//UE5/Release-5.020979098Did not reproduce//UE5/Release-5.123901901Reproduced//UE5/Release-5.224608918Reproduc ...