Unreal Engine Issues
Unreal Engine Issues
Possession is not replicated properly to some clients
UE - Networking - Nov 8, 2018A user has reported an issue where Possession replication or Character Movement replication, unsure of which, is not working properly for some clients. It seems to work fine for the first client but ...
The socketbuilders do not properly join multicast groups on iOS
UE - Networking - Jul 26, 2019On iOS, using the code in the UDP socketbuilders causes the sessions tool to not join with iOS devices. Giving the error EADDRNOTAVAIL. If the user falls back to the other code function that uses th ...
Crash on Mac on exit.
Media Framework - Aug 17, 2020A licensee reported trouble with a crash on exit on Mac. They discovered that the file AvfMediaPlayer.cpp, on the function Open there is this piece of code:// Force the AV player to not be able to ...
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, ...
Editor-only blueprints like WidgetBlueprint are not added to cooked asset registry class hierarchy
UE - CoreTech - Aug 10, 2022Both the Asset Registry and Asset Manager look for all subclasses of UBlueprintCore and use that to search for blueprint classes and construct an inheritance hierarchy. This always works in editor b ...
Switchboard Unable to Launch Multi-User Slate Server in Launcher Builds
UE - Virtual Production - Tools - Switchboard - 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 - Anim - Runtime - 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 - Anim - Gameplay - 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 - Anim - Runtime - 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 ...