Failed to find object 'Class None.'

anonymous_user_2b03d27c · September 12, 2016, 1:47pm

Hey JonTerp-

We are still investigating this issue to narrow down where it is and is not occurring.

nischtz · November 7, 2016, 5:37pm

I’m seeing this warning in all my projects, and pretty much every .log file users posted here. I might have an idea, though…

When starting the engine, the following lines are logged for me:

[2016.10.10-13.59.21:241][ 0]LogContentBrowser: Native class hierarchy updated for ‘SceneOutliner’ in 0.0009 seconds. Added 1 classes and 2 folders.

[2016.10.10-13.59.21:297][ 0]LogCrashTracker: Crashtracker disabled due to settings.

[2016.10.10-13.59.21:306][ 0]LogUObjectGlobals:Warning: Failed to find object ‘Class None.’

[2016.10.10-13.59.21:371][ 0]LogContentBrowser: Native class hierarchy updated for ‘HierarchicalLODOutliner’ in 0.0008 seconds. Added 1 classes and 2 folders.

When closing the engine, the modules are unloaded in reverse order:

[2016.10.10-21.07.18:628][824]LogModuleManager: Shutting down and abandoning module HierarchicalLODOutliner (243)

[2016.10.10-21.07.18:628][824]LogModuleManager: Shutting down and abandoning module CrashTracker (242)

[2016.10.10-21.07.18:629][824]LogModuleManager: Shutting down and abandoning module SceneOutliner (241)

Maybe someone who doesn’t experience this warning could take a look, if there’s a module that is unloaded between HierarchicalLODOutliner and CrashTracker?
(sorry, couldn’t get the formatting right)

CiteNoir · November 16, 2016, 11:56pm

seeing it too, in 4.13 and now in 4.14

anonymous_user_d251ba761 · November 17, 2016, 12:05am

They have it scheduled for fix in version 4.15 but for some reason in the developer notes here they state it has already been fixed.

CiteNoir · November 17, 2016, 12:13am

yeah, that too in the notes. but thanks for the update on the schedule!

I get a few “failed to find object none.none” as well in there. is this related to the class.none thing? they only appeared after switching from 4.13 to 4.14.

ancient-gate · December 4, 2016, 7:38pm

created from clean 4.14 project (first person C++ template)
LogUObjectGlobals:Warning: Failed to find object ‘Class None.’

anonymous_user_dceb25d5 · December 5, 2016, 4:18pm

Same error on cooking a project in 4.14. It’s not a fresh project but it seems like so many other people have this issue I might as well chime in since I could not find the root cause of this in my project.

mindw0rm · December 5, 2016, 11:46pm

I see this warning in 4.14.0 when opening a project without a tutorial in it.

The warning is triggered in StaticLoadObject (in Runtime/CoreUObject/Private/UObject/UObjectGlobals.cpp, lines 872ff), called from a call to LoadClass in FIntroTutorials::MaybeOpenWelcomeTutorial() (in Source/Editor/IntroTutorials/Private/IntroTutorials.cpp, line 329), which is commented with “try project startup tutorial”.

The only meaningful parameter given is *GetDefault()->StartupTutorial.ToString(), which returns an empty string – not surprising, since there is no tutorial.

A fix might be as simple as checking this string for not being empty before calling LoadClass.

Or (since this warning sometimes seems to occur in other circumstances too) maybe LoadClass/LoadObject could even silently return null if the given name is empty? The caller should check for a valid result anyway (which is done here, so no further error occurs). Or change the warning to something like “name must be valid” or “empty object name given to LoadObject”?

anonymous_user_2709d010 · December 10, 2016, 6:35am

I believe this also causes cooking to fail. I can’t cook my project with the same message, just as an error. There needs to be a way to figure out WHERE Unreal detects the NONE so we can fix it in our projects!

syq · December 10, 2016, 9:21am

I also get this error but in my case it refers to my gamemode, because
I intentionally left the default player character to none because I change it
at runtime, so maybe you also have an empty slot inside gamemode, I hope this helps…

anonymous_user_2709d010 · December 11, 2016, 12:23am

Thanks but all my fields in the Project settings are filled out with valid classes.
It is something in my C++ files I believe, that’s going to be one hell of a workload to figure that out

project.gheist · February 23, 2017, 5:35pm

I was able to resolve this issue in PR #3300 (still needs to be reviewed by Epic). The issue was caused by the engine trying to load a startup tutorial from the project settings that was empty.

Hope that resolves the issue for everyone. Cheers,

huulong · May 10, 2017, 4:33pm

Nice, I have subscribed to the PR and I’ll check if the bug is gone in the next version.

anonymous_user_ddbff6561 · July 11, 2017, 8:29pm

I had same warning.
For me the following fixed the problem:

Go to ProjectSettings->Engine->Tutorials
In “Startup Tutorial” dropdown select “EditorTutorial” instead of “None”.

UE Version 4.16.2

Vertex_Soup · July 18, 2017, 8:33pm

I can confirm this is valid for UE4.16.2 message is gone. Thank you!

anonymous_user_dceb25d5 · August 6, 2017, 8:43pm

ya I still get this all the time as well for as long as I can remember, it’s the ol’ class none, an old friend indeed.

Yakim · July 5, 2017, 4:18pm

http://dl4.joxi.net/drive/2017/07/05/0018/2828/1182476/76/ac0f4e1e8d.jpg

Todd.Vance · August 6, 2017, 7:39pm

ha, I’m getting that in August, 2017 with U Engine 4.16.3!

keplerspacepilot · August 12, 2018, 12:42am

I’m also getting this issue! I’ve attempted to fix following advice from this thread, but still the error appears and I think it’s stopping the cook from working. It’s the only error left in my cook log and I’d love to find the solution.

Any other ideas?

MatousLorinc · May 20, 2022, 3:38am

I had this Warning in UE 5.0.0. And cause was I had syntax error in C++ and did not pressed recompile button before build.