Unreal Engine Issues
Unreal Engine Issues
Map placed actor binding to another actor's Event Dispatcher (multicast delegate) results in duplicate bindings after blueprint recompile
UE - Framework - Blueprint - Apr 17, 2025Context Blueprint actors placed on the map can bind to another actor's event. If an ActorB has a reference to ActorA, it can bind to an event dispatcher in A by creating an event node in ActorB's e ...
Changing a Media Player asset from Stream Mode: FromURL to From Memory crashes the editor
Tools - Dec 30, 2014Changing a Media Player asset from Stream Mode: FromURL to From Memory crashes the editor. In 4.8, the editor crashes immediately upon changing that value, with no crash report. In 4.6 and 4.7 Pre ...
Actor blueprint 'bOptimizeBPComponentData' breaks subobject instantiation for runtime spawned actors in cooked builds
UE - Framework - Blueprint Runtime - Aug 29, 2024A user has reported that when an actor blueprint enables Generate Optimized Component Blueprint Data, default instanced objects of components are not properly duplicated in cooked builds. This resul ...
Level Instance Property Override: Actor::Tags overridden pre-CS but clobbered by RerunConstructionScripts with no post-CS re-apply
UE - World Creation - Worldbuilding Tools - May 4, 2026Summary When using the Level Instance Property Override system, overrides applied to `AActor::Tags` are silently lost for Blueprint actors whose Construction Script assigns or appends to `Tags`. The ...
Crash when changing a Play Node's "Sequence" to a Montage
OLD - Anim - Jan 20, 2016I understand that this is not something you're intended to be able to do (Montages aren't used this way), but we should bar the user from inserting a montage into this variable slot. Crash occurs w ...
Compile error during build stage when packaging for tvOS
UE - Platform - Mobile - Dec 9, 2016Compile error packaging for tvOS: Does not affect iOSUATHelper: Packaging (tvOS): UnrealBuildTool: D:\Build\joseph.wysosky_Main\Engine\Source\Runtime\Core\Private\iOS\IOSAppDelegate.cpp(388,12): ...
[CrashReport] Assertion failed on Linux: SharedContext.hGLContext in OpenGLLinux.cpp
UE - Platform - Linux - Jun 16, 2017This is a top community crash occurring on Linux. The two linked CrashGroups have nearly identical callstacks. A log file is attached. Additional information is currently unavailable. Callstack f ...
[CrashReport] Assertion failed: TaskDataArray.Num() == Exporter->VolumetricLightmapTaskGuids.Num()
UE - Graphics Features - Lumen - Oct 2, 2017This is a trending crash coming out of the 4.18 Previews. Users have not provided any descriptions of their actions when the crash occurred, but at least two of the affected projects are being creat ...
[CrashReport] UE4Editor-MetalShaderFormat.dylib!FGenerateMetalVisitor::print_constant()
UE - Graphics Features - Sep 22, 2017This is an early trending crash coming out of the 4.18 previews. It occurs on Mac, and all affected project names indicate it is related to AR. Users have not provided any descriptions of their ac ...
[CrashReport] Linux crash - FScopeContext::FScopeContext()
UE - Platform - Linux - Oct 5, 2017This is a somewhat common Linux crash occurring in 4.17.2. (there are a few older records in 4.16.2 and 4.17.1 also, but most occur in 4.17.2) Callstack from Log[2017.10.04-14.49.42:768][ 2]LogFi ...