UEFN cook_failure since latest update – Array index out of bounds during cook

Summary

Hello,

Since the latest Fortnite / UEFN update, my project no longer cooks or launches correctly.
Before the update, the project was working, but now I get a cook failure when trying

I already tried creating another almost empty level / removing content, but the cook error still happens, so I’m not sure if the issue is coming from a corrupted actor, runtime data layers, or something introduced by the latest update.

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Live Edit

Steps to Reproduce

launch session

Expected Result

run the session

Observed Result

PlatformCook: Error: Nous avons subi une erreur en préparant ce contenu.
PlatformCook: Error: cook_failure
LogWindows: Error: appError called: Assertion failed:
(Index >= 0) & (Index < ArrayNum)
[File: Z:\UEVFS\Root\Engine\Source\Runtime\Core\Public\Containers\Array.h] [Line: 1339]
Array index out of bounds: 15 into an array of size 14

Platform(s)

pc

Island Code

7563-7108-6934

Upload an image

bug1.png