Unreal Engine instant crash after opening this project

This is the error:

Fatal error: [File:D:\Build\++UE4+Release-4.12+Compile\Sync\Engine\Source\Runtime\Foliage\Private\FoliageInstanceBase.cpp] [Line: 90] 
Instance base cache - integrity verification(3): Counter: 7 Size: 5, InvSize: 4 (L:1 S:0 T:0)


UE4Editor_Core!FDebug::AssertFailed() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:440]
UE4Editor_Foliage!operator<<() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\foliage\private\foliageinstancebase.cpp:93]
UE4Editor_Foliage!AInstancedFoliageActor::Serialize() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\foliage\private\instancedfoliage.cpp:2247]
UE4Editor_CoreUObject!FLinkerLoad::Preload() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\coreuobject\private\uobject\linkerload.cpp:3293]
UE4Editor_CoreUObject!EndLoad() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:1411]
UE4Editor_CoreUObject!LoadPackageInternal() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:1171]
UE4Editor_CoreUObject!LoadPackageInternal() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:1286]
UE4Editor_UnrealEd!UEditorEngine::Map_Load() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\editorserver.cpp:2397]
UE4Editor_UnrealEd!UEditorEngine::HandleMapCommand() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\editorserver.cpp:5987]
UE4Editor_UnrealEd!UEditorEngine::Exec() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\editorserver.cpp:5477]
UE4Editor_UnrealEd!UUnrealEdEngine::Exec() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\unrealedsrv.cpp:744]
UE4Editor_UnrealEd!FEditorFileUtils::LoadMap() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\filehelpers.cpp:2135]
UE4Editor_UnrealEd!FEditorFileUtils::LoadDefaultMapAtStartup() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\filehelpers.cpp:3349]
UE4Editor_UnrealEd!FUnrealEdMisc::OnInit() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\unrealedmisc.cpp:300]
UE4Editor_UnrealEd!EditorInit() [d:\build\++ue4+release-4.12+compile\sync\engine\source\editor\unrealed\private\unrealed.cpp:89]
UE4Editor!GuardedMain() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\launch.cpp:137]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [d:\build\++ue4+release-4.12+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:200]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll

Hey BCarvalho98,

Thanks for the report. It appears that this issue has already been logged as issue: UE-32774 and is currently being handled by the development staff.

Thank you for the quick answer, is there a way to continue working? Like an old save?

My best advice is to try and revert back to a version where the project was working. If that is not possible, you can try backing up and then removing the default map for the project, to see if you can get the editor to launch without this crash.

This crash did not occur in 4.11 and the maps have not been modified, so a code change is the cause of this. This crash will also occur during cook.

Hi guys,
I’ve been encountering this crash pretty frequently as well. Reverting the work back to a previous state is working, hoping for a fix soon!

Hey! What’s the current status of UE-32774? Is a fix planned for a 4.12 hotfix, or is there a CL number we could pull to fix this issue?

This is a pretty big problem for us.

Thanks.

It looks like it will be fixed in 4.13 but if 4.13 is released and you are still having this issue, please let us know and we can re-investigate.

Given how blocking it is for our workflow, we won’t be able to wait for 4.13. Is there a Perforce CL number you could gave us so we can run the integration manually on our side?

Hey Samuel,

The current status of the issue is still not fixed.

As for a future CL number, I recommend making a post on the UDN so we can further assist.

Here’s the UDN post:
https://udn.unrealengine.com/questions/303611/412-fix-needed-for-foliage-crash-ue-32774.html

Hi,

Sorry about these troubles. We found several cases where Editor operations were breaking some assumptions in foliage (some of Undo/Redo operations, level SaveAs, level Duplicate). These should be fixed with CL# 3032336, 3057039 (scheduled for 4.13). Could you integrate these changes? These changes also remove asserts in foliage at loading time, so even if level was already saved with some broken foliage, Editor will still load that level without crashing. Broken foliage will lose a link to a component on which it was painted on (moving that component will not move foliage instances). These can be postfixed in Editor by Snapping foliage instances to ground (select instances + End key). If you can’t integrate those CLs I would recommend to replace all entries of:

UE_LOG(LogInstancedFoliage, Fatal 
to 
UE_LOG(LogInstancedFoliage, Error  

in FoliageInstanceBase.cpp. That at least will allow to load crashing level in the Editor.

is there a workaround on this?
It’s corrupting my scene very often and rollback is never fun

Instance base cache - integrity verification(3) is the exact same error i got when i dared to press simulate in the editor. now it doesnt open anymore, cant edit anything so basically one month of work is just gone because of this ----- engine! its awful to work with, unneccesary complicated and once you got the hang of it, it just crashes and ruins all of your work. thanks, really!