Unreal Engine Issues
Unreal Engine Issues
FKeyHandle internal static atomic counter can overflow on long running games depending on usage pattern
UE - Runtime - Animation - Sep 24, 2025Structure FKeyHandle stores an internal index, which is initialized from a static atomic counter in the default constructor: +----- FKeyHandle::FKeyHandle() { | static std::atomic<uint32> LastKey ...
ENGINE: CRASH: One off Editor Crash with ANavLinkProxy::GetComponentsBoundingBox() navlinkproxy.cpp:189
UE - AI - Oct 20, 2016One off editor crash. [Link Removed] Error Message Access violation - code c0000005 (first/second chance not available) Call Stack of Most Recent Crash ANavLinkProxy::GetComponentsBoundingBox() na ...
Once an actor channel is closed by NetCullDistance, root motion movement synchronization stops working
UE - Framework - Networking - Jul 12, 2021Properties that uses DOREPLIFETIME_ACTIVE_OVERRIDE (ex. RepRootMotion ) will also skip replication when an actor channel is newly opened. This means that if the variables on the server side do not c ...
[PCG Mode] Tool actors spawned by PCG Editor Mode tools ignore the current level and are always created in the PersistentLevel
UE - Graphics Tools - PCG - Procedural Tools - Oct 21, 2026Summary In a non-World-Partition map with streamed sublevels, PCG Editor Mode interactive tools (Draw Spline / SpacingTool, Area, Paint, Volume, ...) spawn their new tool actor in the PersistentLevel ...
Crash in AWorldDataLayers::InitializeDataLayerRuntimeStates() when quickly unloading then loading a sub-world partition
UE - Engine Scaling - Streaming - Data Layers - Mar 6, 2025From licensee: Since we integrated 5.5, we are experiencing a crash in AWorldDataLayers::InitializeDataLayerRuntimeStates() on this line check(ActiveDataLayerNames.IsEmpty() && LoadedDataLayerN ...
Crash on iOS9 when using Apple's CFNetwork library
UE - Platform - Mobile - Dec 6, 2016Many clients have hit a crash due to an Apple library using operator delete on a memory block that was not allocated with operator new. This happens with the following callstack on iOS9 in UE4.13 o ...
Loading a blueprint with an invalid gameplay tag container pin causes ensure and data loss
UE - Gameplay - Feb 23, 2021The gameplay tag system depends on tags being registered with the global manager as valid in order to correctly read them off disk. Two different issues are combining to cause a confusing ensure and ...
If using SetAlignmentInViewport in Construct, the value with it is ignored
UE - AI Workflows - UI Systems - UMG - Jan 27, 2023If SetAlignmentInViewport is called in the UMG Construct, it is ignored internally. This is due to a change that came in 5.1, so it worked fine in 5.0. First, when the Set Alignment in Viewport nod ...
Launching QAGame for HTML5 creates an 'uncaught exception: out of memory'.
UE - Platform - Mobile - Jan 18, 2017Launching onto HTML5 opens the browser to Uncaught Exception: out of Memory After running it on a 64-bit browser, the following is printed:uncaught exception: abort("Cannot enlarge memory arrays. E ...
[CrashReport] UE4Editor_SlateRHIRenderer!FSlateRHIResourceManager::GetShaderResource() [slaterhiresourcemanager.cpp:525]
UE - Editor - UI Systems - Slate - Nov 2, 2017This is a trending crash coming out of the 4.18 release, and may be a regression. Users have not provided any descriptions of their actions when the crash occurred. Jiras for similar callstacks in ...