Unreal Engine Issues
Unreal Engine Issues
OSS Steam: SteamSocket listen connections do not work after poll group changes
UE - Online - Oct 25, 2021In 4.27 the logic in SteamSocket.cpp which is part of the SteamSockets plugin was changed to use Poll Groups instead of a removed API function that checked all children of a listen socket. However, ...
Switchboard Unable to Launch Multi-User Slate Server in Launcher Builds
zComponent - Archive - Jan 14, 2023Switchboard is unable to launch the Multi-User Slate Server in launcher builds. This is because the default install location has "Program Files and "Epic Games" in the path (aka folders with spaces ...
Animation attributes - user defined structs containing types defined in plugins cannot be registered
UE - Runtime - Animation - Dec 18, 2023This issue is caused by us forcing user defined structs to be loaded as part of AttributeTypes::Initialize. That is called after at the ObjectSystemReady run phase during engine initialization howe ...
Placing a section at the end of montage is not properly handled
UE - MVF Character - Animation - Feb 24, 2024Placing a section at the very end of a montage with no duration or animation assigned after it is not properly handled. Normally sections with 0 length are skipped and search continues since they ...
Packed Level Actors will create ISMs with inverted normals when a portion of static meshes have negative scales. This is apparent with two-sided materials.
UE - World Creation - Worldbuilding Tools - Feb 17, 2025Packed level actors will create ISM instances with inverted normals when the selection of meshes used to create the packed level actor contains a subset of meshes with negative scales. This is the ...
FAnimMontageInstance::SetNextPositionWithEvents can trigger all notifies on a montage/sequence
UE - Runtime - Animation - Jun 24, 2025This issue happens when Sequencer loops a dynamic montage. FAnimMontageInstance::ForcedNextFromPosition is set to 0 and ForcedNextToPosition is effectively the delta time. However, FMontageSubStep ...
Performance slowdown when ray tracing is disabled due to SetResidencyPriority
UE - Rendering - Architecture - RHI - Jul 17, 2025When a game is compiled with ray tracing disabled (D3D12_RHI_RAYTRACING=0) and the GPU the game is running on becomes low on VRAM, frame time is negatively impacted and doesn't recover. The D3D12_RH ...
Crash when exporting Static Meshes as an FBX (UE4Editor-SlateCore.dll!SWidget::OnQueryShowFocus)
Tools - Sep 21, 2017Possibly related to [Link Removed] ...
Crash on Device when Deploying Mobile Project with Modulated Shadows and Planar Reflections on iOS 9
UE - Platform - Mobile - Jan 6, 2017A crash occurs on iOS when deploying the licensee's project using iOS 9 version. The crash does not occur when deployed to a device using iOS 10 version. They believe the crash to be related to Pl ...
Bad references for Lighting Scenarios when moving Levels and Map Build Data Registry to different Folder
Tools - Feb 2, 2017When moving Lighting Scenario Levels and their associated Map Build Data Registry to a new folder within the Content Browser, the references within the Levels tab are updated as [MapName_BuiltData]. ...