Unreal Engine Issues
Unreal Engine Issues
AssetRegistry: In a packaged game ScanPathsSynchronous with bForceRescan=true will permanently forget about assets inside IOStore containers
UE - Core - Data Pipeline - May 7, 2025This came up from several discussions on UDN and internal discussion. The root cause is that the AssetRegistry currently cannot discover packages inside IOStore containers, it relies on the seriali ...
Non-determinism in StaticMeshComponent::BodyInstance when cooking LevelInstances
UE - Runtime - Simulation - May 21, 2026A licensee reported that serialization of LevelSequence with StaticMeshActor with default collision for which mesh has NoCollision profile is not deterministic. The issue seems to be in the fact tha ...
CPF_TextExportTransient and RF_TextExportTransient inconsistent behavior
UE - Framework - Blueprint - May 23, 2024The TextExportTransient can be specified as a property flag and object flag. Behavior is inconsistent: there are many ways in which an object marked TextExportTransient can still be part of the text ...
Deleting transient actor marks level dirty
UE - World Creation - Worldbuilding Tools - Feb 6, 2025The licensee has noticed that the deletion of a transient actor still marks the scene as dirty and asks it to be saved. Checking the source it was noted that the transient flag is not verified on de ...
Focus mode in the Editor does not handle Actors without PrimitiveComponent correctly, treating them as if they were at the origin (0,0,0), skewing the camera placement.
UE - World Creation - Worldbuilding Tools - Nov 18, 2024Focus mode in the Editor does not handle Actors without PrimitiveComponent correctly, treating them as if they were at the origin (0,0,0), skewing the camera placement. Some Actors like the WorldDat ...
Spawnable Level Instance via Sequencer in WP map
UE - World Creation - Worldbuilding Tools - Level Instances - Aug 21, 2023ULevelInstanceSubsystem::OnActorDeleted: check(!IsEditingLevelInstanceDirty(LevelInstance) && !HasDirtyChildrenLevelInstances(LevelInstance)); ...
Deprecated blueprint variable fixups may fail depending on loading order
UE - Framework - Blueprint - Mar 7, 2024There is currently no simple way to do a deprecated variable fixup on native variables that are set by a blueprint class. For a simple variable rename, CoreRedirects can be used and will work proper ...
FBX Export - StaticMesh export to FBX crashes if UVElements has more channels than VertexInstanceUVs
UE - Editor - Content Pipeline - FBX - Jan 22, 2026As indicated in the repro steps, we have a StaticMesh asset that, for some reason, has a mismatch in their serialized bulk data where:MeshDescription->GetNumUVElementChannels() == 2FStaticMeshConstA ...
Placed level instance causes "!ActorInstanceGuid.IsValid()" assertion after changing WorldSettingsClass
UE - World Creation - Worldbuilding Tools - Level Instances - Nov 13, 2023Resaving the level using ResavePackagesCommandlet is a workaround. ...
Copying a Folder that contains the space character from the Outliner does not enclose the Folder name on Double Quotes. Because of that, later Pasting will only handle the first word of the Folder name.
UE - World Creation - Worldbuilding Tools - Jun 10, 2025Copying a Folder that contains the space character from the Outliner does not enclose the Folder name on Double Quotes. Because of that, later Pasting will only handle the first word of the Folder n ...