I periodically get a packaging error that only occurs on child blueprints.
It causes an unrecoverable assertion:
Assertion failed: !Export.ClassIndex.IsNull() [File:C:/OUE/Engine/Source/Runtime/CoreUObject/Private/UObject/SavePackage.cpp] [Line: 3807]
Export SKEL_ZombiePC_C /Game/XXXXXX/Zombie/ZombiePC.Default__SKEL_ZombiePC_C class is not mapped when saving /Game/XXXXXXXXX/Zombie/ZombiePC
UE4Editor-Win64-DebugGame.exe has triggered a breakpoint.
I can typically relaunch and repackage without issue.
It has happened on multiple child blueprints.
Thanks for any help
[UPDATE] So this is definitely annoying. Will get crash when launching to device if there is a child blueprint of a blueprint referenced. Typically, you can simply realunch editor and package right away and it works. Doing work in the editor causes some kind of error to happen when packaging with a child blueprint.
As if launching to device in Unreal wasnt already pretty slow... now it susually crashed and I have to relaunch editor 😞
Found a solution that worked for me by going into Saved/Cooked and Saved/EditorCooked locating the file and removing both the Uasset and Uexp version of it, then relaunching. or repackaging. Hope this will help someone.
I had same issue. CDO from transient class is not marked as transient after blueprint regeneration.
This change fixed it for me https://github.com/EpicGames/UnrealEngine/commit/abfa80bb9565a6f61fe236008654bcc8dc460959