Editor Crashed: Access violation after pressing play or compile button

When I pressed the play button or the compile button on my project, then unreal editor was crashed.

Branch: ‘Binary’ build from the Unreal Launcher

Version: 4.7.6-2513093+++depot+UE4-Releases+4.7

System: Windows 8.1

Reproduce Steps:

  1. Load my project.
  2. Press the play or compile button.

The issue occur very frequently.

The crash log:
Crash Log

Access violation - code c0000005 (first/second chance not available)

UE4Editor_CoreUObject!UObjectBase::IsValidLowLevelFast() + 118 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\uobjectbase.cpp:306]
UE4Editor_CoreUObject!FGCCollector::HandleObjectReference() + 83 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\garbagecollection.cpp:269]
UE4Editor_Engine!FSimpleObjectReferenceCollectorArchive::operator<<() + 77 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\public\uobject\garbagecollection.h:460]
UE4Editor_CoreUObject!UObjectProperty::SerializeItem() + 55 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\propertyobject.cpp:32]
UE4Editor_CoreUObject!UStruct::SerializeBin() + 254 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\class.cpp:715]
UE4Editor_Engine!UBlueprintGeneratedClass::AddReferencedObjectsInUbergraphFrame() + 744 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\engine\private\blueprintgeneratedclass.cpp:700]
UE4Editor_CoreUObject!FArchiveRealtimeGC::ProcessObjectArray() + 7509 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\coreuobject\private\uobject\garbagecollection.cpp:707]
UE4Editor_CoreUObject!TGraphTask<FArchiveRealtimeGC::FGCTask>::ExecuteTask() + 453 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\public\async\taskgraphinterfaces.h:671]
UE4Editor_Core!FTaskThread::ProcessTasks() + 3125 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\async\taskgraph.cpp:428]
UE4Editor_Core!FTaskThread::ProcessTasksUntilQuit() + 77 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\async\taskgraph.cpp:271]
UE4Editor_Core!FTaskThread::Run() + 11 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\async\taskgraph.cpp:562]
UE4Editor_Core!FRunnableThreadWin::Run() + 102 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\windows\windowsrunnablethread.cpp:73]
UE4Editor_Core!FRunnableThreadWin::GuardedRun() + 93 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\core\private\windows\windowsrunnablethread.cpp:26]
kernel32 + 5074 bytes
ntdll + 452948 bytes

Hi HamkenDevelop,

Can you post your dxdiag here so i can take a look? Additionally, does this occur with a clean project with no additional content or is it limited to a specific project?


Thank you for a response.

Dxdiag is here.

And this is a backup log of when the editor crashed.

My project has a lot of additional contents and also a component that made with c++.

What was the most recent addition to your project before the crashes began occurring? Have you checked your C++ component code to ensure that it isn’t missing any code formatting (semicolons, matching capitalization, etc)?

I added a blueprint component to my project before the crashes began occurring.

I added a c++ component to my project a month ago. At that time the issue did not occur.
So I would like to think that there are no missing point in my c++ component.

The most likely scenario is that your C++ is fine, I just want to eliminate the easy fixes as I work through to try and limit what the possible bug could be. What is in your blueprint component script?

What is revealed is that the crash has not occurred after my blueprint component compiled.
But the issue occurs again after exiting the editor and reopening my project.

What is my blueprint component:

It is named BP_BuildStage.
It acts spawning pawns and ornaments at the game’s starting up. It is attached to my game mode class.

My game mode class has have two components.


One is AutoBuildMap that is c++ component.
The other is BP_BuildStage that is blueprint component.
The BP_BuildStage access the AutoBuildMap.

This is BP_BuildStage’s Event Graph.

I’m going to have you try a few things, to rule out possibilities. The first is, when you close and re-open the editor, try compiling the blueprint(s) before pressing play. Does it crash after doing this?

When I compile the BP_BuildStage (blueprint component) first, the editor does not crash. Subsequently, pressing the play button and the compile button on the other blueprint does not cause a crash anymore.

When I compile the other blueprint first, the editor crashes.

What does the other blueprint do specifically? Can you show me what is in that event graph?

I think that they do not especial something.

Additional crash reporting:

After my project loaded, when I exit the editor first, then the editor are crashed.

in this other blueprint, do you have any cast nodes, struct calls, interfaces, or other blueprint communication nodes that you are using?

I inspected all my blueprints for cast nodes and interface call nodes.

The blueprints list is below.

The Blueprints List

Which other blueprint is the one that crashes the editor specifically? Can you show me the event graph of the blueprint that is causing the crash?

I added new blueprint that had empty event graph. After reloading my project, pressing the compile button on this blueprint caused the crash.
This blueprint is not in communication with another blueprints.

Did you add any components to the blueprint? Can you show me your components viewport and what is in there?

Nope. I did not add any component to its blueprint. Also, I did not modify it. It is initial setting and is inheriting the Actor class.

If you delete this blueprint do the crashes stop occurring?

After deleting it, the crash occurred still.

Can you send me a copy of your project? I’ll take a look and see what is going on. If you prefer to keep your project private, you can private message me a link to the project on the forums and I’ll pull it from there.