This is a common engine crash that has occurred since at least 4.16. Users have not provided any useful descriptions of their actions when the crash occurred.

The callstack shares some similarities to [Link Removed]. The callstack is also frequently seen in an Ensure that shares the same crashGroup, and the error message of that Ensure references Object->IsValidLowLevelFast, which again is similar to [Link Removed].

Source Context

 3318       protected:
 3319       	virtual FArchive& operator<<(UObject*& Object) override
 3320       	{
 3321       #if !(UE_BUILD_TEST || UE_BUILD_SHIPPING)
 3322       		if (!ensureMsgf((Object == nullptr) || Object->IsValidLowLevelFast()
 3323       			, TEXT("Invalid object referenced by the PersistentFrame: 0x%016llx (Blueprint object: %s, ReferencingProperty: %s) - If you have a reliable repro for this, please contact the development team with it.")
 3324       			, (int64)(PTRINT)Object
 3325       			, SerializingObject ? *SerializingObject->GetFullName() : TEXT("NULL")
 3326       			, GetSerializedProperty() ? *GetSerializedProperty()->GetFullName() : TEXT("NULL")))
 3327       		{
 3328       			// clear the property value (it's garbage)... the ubergraph-frame
 3329       			// has just lost a reference to whatever it was attempting to hold onto
 3330 ***** 			Object = nullptr;
 3331       		}
Steps to Reproduce

repro steps currently unknown

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

UE4Editor_CoreUObject!FPersistentFrameCollectorArchive::operator<<() uobjectglobals.cpp:3331 
UE4Editor_CoreUObject!UStruct::SerializeBin() class.cpp:837 
UE4Editor_Engine!UBlueprintGeneratedClass::AddReferencedObjectsInUbergraphFrame() blueprintgeneratedclass.cpp:1428 
UE4Editor_CoreUObject!TFastReferenceCollector<1,FGCReferenceProcessor<1>,FGCCollector<1>,FGCArrayPool,0>::ProcessObjectArray() fastreferencecollector.h:775 
UE4Editor_CoreUObject!TFastReferenceCollector<1,FGCReferenceProcessor<1>,FGCCollector<1>,FGCArrayPool,0>::FCollectorTaskQueue::DoTask() fastreferencecollector.h:381 
UE4Editor_CoreUObject!TGraphTask<TFastReferenceCollector<1,FGCReferenceProcessor<1>,FGCCollector<1>,FGCArrayPool,0>::FCollectorTaskProcessorTask>::Exe taskgraphinterfaces.h:784 
UE4Editor_Core!FTaskThreadAnyThread::ProcessTasks() taskgraph.cpp:910 
UE4Editor_Core!FTaskThreadAnyThread::ProcessTasksUntilQuit() taskgraph.cpp:786 
UE4Editor_Core!FTaskThreadBase::Run() taskgraph.cpp:502 
UE4Editor_Core!FRunnableThreadWin::Run() windowsrunnablethread.cpp:76 
Community References

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Won't Fix
ComponentUE - Gameplay - Blueprint
Affects Versions4.
CreatedNov 2, 2017
ResolvedAug 18, 2021
UpdatedAug 18, 2021