4.7 preview 3, crash on play

ver 4.7 preview 3, crash on play

i update 4.7 preview 2 to preview 3

  • if i load my project, play option work good !!!
  • i have crash in play mode always when i add smth new (example mesh, nomatter what mesh)


Unknown exception - code 00000001 (first/second chance not available)

Assertion failed: !InTemplate || InTemplate->IsA(InClass) || (InFlags & RF_ClassDefaultObject) [File:D:\BuildFarm\buildmachine_++depot+UE4-Releases+4.7\Engine\Source\Runtime\CoreUObject\Private\UObject\UObjectGlobals.cpp] [Line: 2180]

KERNELBASE + 24684 bytes
UE4Editor_Core + 3140052 bytes
UE4Editor_Core + 1614600 bytes
UE4Editor_Core + 1494994 bytes
UE4Editor_CoreUObject + 1578640 bytes
UE4Editor_CoreUObject + 490124 bytes
UE4Editor_CoreUObject + 275339 bytes
UE4Editor_CoreUObject + 1649721 bytes
UE4Editor_CoreUObject + 1311032 bytes
UE4Editor_CoreUObject + 1561945 bytes
UE4Editor_CoreUObject + 719834 bytes
UE4Editor_CoreUObject + 719382 bytes
UE4Editor_CoreUObject + 1164812 bytes
UE4Editor_CoreUObject + 1156901 bytes
UE4Editor_CoreUObject + 1582370 bytes
UE4Editor_CoreUObject + 1580274 bytes
UE4Editor_UnrealEd + 4357407 bytes
UE4Editor_Engine + 3564395 bytes
UE4Editor_UnrealEd + 4348176 bytes
UE4Editor_UnrealEd + 4647931 bytes
UE4Editor_UnrealEd + 4747379 bytes
UE4Editor_UnrealEd + 1837729 bytes
UE4Editor_UnrealEd + 6723958 bytes
UE4Editor!FEngineLoop::Tick() + 4084 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\launchengineloop.cpp:2240]
UE4Editor!GuardedMain() + 479 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\launch.cpp:131]
UE4Editor!GuardedMainWrapper() + 26 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() + 249 bytes [d:\buildfarm\buildmachine_++depot+ue4-releases+4.7\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__tmainCRTStartup() + 329 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]

Hello dev666rej,

We are sorry to hear you are experiencing this crash. Would you mind providing me with your ‘dxdiag’?

Also are you attempting to add an asset while in ‘Play’ mode?

Thank you,

Also are you attempting to add an asset while in ‘Play’ mode?

only when i add some meshes in editor and go to play mode, in moment when editor wanna start play mode i have this crash

i notice smth interesting, when i save project, after add some meshes, and go to play mode , everything its okey

Although this might sound tedious, if you are adding a lot of meshes before you press the play button, it might be best for you to save anyway. This will ensure you don’t lose any important placements or sizes that you set for a specific mesh or asset.

Another question, what types of meshes are you talking about. Are these all ‘Static Mesh’ objects, or is this anything like ‘BSP’ to a ‘Particle Effect’?

I should have mentioned this before, but all we need is for you to attach your dxdiag via the attach button here on the AnswerHub.


i add only one static mesh, exapmle, simple box, only one static mesh make crash if i start play button, if i not save befor start button of course, i now very good about saving after adding meany meshing, but its crash after one simple mesh, link text

video from crash

Unfortunately this seems very project related. The only way for me to test this would be to test your entire project which is unnecessary.

The video you provided is great and gives us a visual for how the crash is reproduced!

I like to provide this link on How to Report a Crash on the AnswerHub because it provides us with the most information possible so we can attempt to find the source of the crash, and a potential solution.

How to Report a Bug/Crash on AnswerHub

If you just attach your .LOG and .DMP files the information you have provided to me should be sufficient.

Thanks again,

Apologies I totally linked you to the wrong information! haha


I’ve stumbled upon this bug also. Found 100% repro case. Test project is attached.

Repro steps:

  1. create new level

  2. add Trigger Box and add OnActorOverlapBegin event to this trigger in level blueprint

  3. save and restart level (restarting level is optional, I think…)

  4. add another Trigger Box to level (simple drag to viewport) and hit play (make sure NOT to save level before hitting play)

TestLevel_P contains base setup. Please open it, add trigger and hit play. Observe engine crashing.

Tested on Binary 4.7.0. Preview 4 and code commit 56fb443

Hello theDrunkenBunny,

Thank you for the bug report, but we ask that users post any new reports as a new AnswerHub post for tracking purposes. This makes sure that if the bug experienced by others, they can quickly search for the issue and find a proper resolution.


My meshes is working fine but whenever i add Foliage with the foliage tool it crashes immediately,but i can add a tree separately but cant use foliage at all and all my level’s that have foliage don’t want to open up :(… but it is okey i’l wait for the next update, placing foliage with hand now and not with the tool hahaha :slight_smile:

Hi Andrew,

I was debating over posting this in here or in new thread. I will follow you suggestion next time.

I’ve seen that this crash has been fixed in 4.7. branch.

Hi Andrew

"Meybe better Close This Topic, in the preview 4 this bug was fixed.