Metahuman crashes when I'm compiling identity

General Issues and Bug Reporting
, , ,
1

Summary

My unreal version is 5.6, it’s crashes with error “The package to load does not exist on disk or in the loader” and "Error: appError called: Assertion failed: IsThisNotNull(this, “UStruct::IsChildOf”) [File:D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Class.cpp] [Line: 2743] "

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Character

Steps to Reproduce

  1. Make new metahuman character
  2. Compile him

Expected Result

It should compily my metahuman character for work

Observed Result

It’s crashes Unreal

Platform(s)

Windows

2

I get the same issue when I try to build/cook my game. I don’t use this IsChildOf function in my codebase and it’s rather hard to track down where the issue lies.

1 Like
3

Yep confirmed this on PC Windows. Can’t build with Metahumans plugins activated.

1 Like
4

This was mentioned in the 5.6 release thread + a possible workaround: Unreal Engine 5.6 Released - #119 by unit23

1 Like
5

Exactly the same issue with my RPG Engine project. After making some changes (removed unnecessary data assets), this error appeared:

Assertion failed: IsThisNotNull(this, “UStruct::IsChildOf”) [File:D:\build++UE5\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Class.cpp] [Line: 2758]

1 Like
6

Another mention here regarding this issue: https://forums.unrealengine.com/t/unreal-engine-5-6-released/2538952/300

7

Considering my post here, I did have the MetaHuman plug-in enabled. Looks like the cook is about to succeed here with it turned off. I’ll do more and check in on this to confirm on my end too.

Then again, looking at the MetaHuman plug-in’s content blueprints, funnily enough, there’s a lot of busted blueprints :melting_face: . Was it this way as well in 5.6.0? Would love to use the MetaHuman plug-in but if it’s at the cost of a 1 out of 10 build succeeding, I would deal with the former :confused: .

8

Responding to my post here. I guess it’s not necessarily the MetaHuman plug-in. It successfully build after disabling it. However, it failed when I attempted to package build again sadly. I did make a post here that seems very consistent to actually making builds work (if you’re in the Unreal Source Discord server . check here if you wanna see the post), but yea it seems I have to deleted the DerivedDataCache, Binaries, Intermediate and Saved folder after every single build in order for the builds to succeed consistently with 5.6.1 . It’s a weeiiirrrdd phenomena, but :person_shrugging: I really don’t know a better solution to this unless Epic can resolve this issue.