After migration to 4.10 launch crash the editor

After having converted the project from 4.9.2 to 4.10 when I start the Play button, it fails in

void UPathFollowingComponent::RecacheNavigationData()
	if (MovementComp != NULL)
		const FNavAgentProperties& NavAgentProps = MovementComp->GetNavAgentPropertiesRef();

		if (ensure(GetWorld() && GetWorld()->GetNavigationSystem()))
			MyNavData = GetWorld()->GetNavigationSystem()->GetNavDataForProps(NavAgentProps);
			// we should get something by now!

The var MyNavData is NULL.

Is there something to do with IA navigation ?


Hey domzorg-

Could you provide the callstack and the log files from the crash as well? I’m also not sure how you’re using the code snippet, can you reproduce the crash in a new project and if so, please include the steps that caused the crash.


Doug Wilson

Some issue. Crash, when editor running from Xcode, then press Play. Map have only empty character on scene.

Thread 6#0	0x000000010c469f64 in UPathFollowingComponent::RecacheNavigationData() ()
#1	0x000000010c498b07 in TBaseUObjectMethodDelegateInstance<false, UPathFollowingComponent, void ()>::ExecuteIfSafe() const ()
#2	0x00000001019d0354 in TBaseMulticastDelegate<void>::Broadcast() const ()
#3	0x00000001025883ec in UNavigationSystem::OnWorldInitDone(FNavigationSystemRunMode) ()
#4	0x0000000101c5e240 in UGameInstance::StartPIEGameInstance(ULocalPlayer*, bool, bool, bool) ()
#5	0x0000000107bb7fe8 in UEditorEngine::CreatePIEGameInstance(int, bool, bool, bool, bool, float) ()
#6	0x0000000107bad746 in UEditorEngine::PlayInEditor(UWorld*, bool) ()
#7	0x0000000107b99b68 in UEditorEngine::StartQueuedPlayMapRequest() ()
#8	0x0000000107875758 in UEditorEngine::Tick(float, bool) ()
#9	0x0000000107f2c4dc in UUnrealEdEngine::Tick(float, bool) ()
#10	0x000000010001e602 in FEngineLoop::Tick() ()
#11	0x0000000100025fa3 in GuardedMain(wchar_t const*) ()
#12	0x0000000100034e3f in -[UE4AppDelegate runGameThread:] ()
#13	0x00000001001da9eb in -[FCocoaGameThread main] ()
#14	0x00007fff8dc73ee4 in __NSThread__start__ ()
#15	0x0000000109e5e815 in _pthread_body ()
#16	0x0000000109e5e792 in _pthread_start ()
#17	0x0000000109e5bfad in thread_start ()

same crash here.

I solved the problem by removing all IA with animation problems. I think the animation blueprints I was using were not compatible with version 4.10. Was working with 4.9.2

With a new project, I don’t have the problem. Since I think it was linked with these animation blueprints.


I had same “ensure” issue after migrating to 4.10. Deleting the only ACharacter I had placed in my map made the problem go away.