Crash when open WBP with wrong event binding

General Issues and Bug Reporting
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1

Summary

My UEFN crash while working on huge WBP. Some binding was empty as this moment (particularly event).

Since, I can’t open the WBP back as it crash the editor instantly.

In .log I got error though binding, making it crash. Fix validation issues doesn’t work to.

[479]LogBlueprint: Error: [AssetLog] /XXX/UIKit/Blueprint/WBP_Shop.WBP_Shop: [Compiler] Event 'WBP_Product_Row_13.BuyInCashProduct1.On Clicked => ()': A source path is required, but not set.
[2026.02.12-12.35.16:200][402]LogOutputDevice: Error: === Handled ensure: ===
[2026.02.12-12.35.16:200][402]LogOutputDevice: Error: 
[2026.02.12-12.35.16:200][402]LogOutputDevice: Error: Ensure condition failed: !AssetData.PackageName.IsNone()  [File:Z:\UEVFS\Root\Engine\Source\Runtime\AssetRegistry\Private\AssetRegistryHelpers.cpp] [Line: 329] 
[2026.02.12-12.35.16:200][402]LogOutputDevice: Error: Failed to find asset data for package: /AnimTools/Assets/ControlRigMacros/ControlRigMacros.ControlRigMacros_C

Currently can’t reopen WBP

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

UI/Tools

Steps to Reproduce

Create WBP with a lot of binding (I’ve more than 200).
Add new event variable
Bind them without select output

Expected Result

Compilation error but nothing else

Observed Result

Crash UEFN. Can’t re-open blueprint back, so it’s a dead uasset currently

I can’t open it, duplicate, rename, move, or delete it

Platform(s)

Windows

2

Having same issue with another WBP, with arround 100 bindings, and without any error. I’ve restart UEFN and can’t open it now

Look like binding quantities related instead of error binding

Opening Widget Crashes Editor
4

More info :

  • the WBP still usable in game, so it look like editor related only
  • I can see the meta data of WBP, and reads the variables, so that’s probably arround the loading of bindings, and not the variables. It crash only in WBP editor

It happened arround 90% of WBP loading

5

FORT-1057575 has been ‘Closed’ as a duplicate of an existing known issue. Origin Issue: FORT-1030147, Origin Topic: MVVM ViewBinding in UserWidget causes cook failure and permanently corrupts the widget

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