# New Update Causes UEFN to Crash on 0% Load Every Time

**URL:** <https://forums.unrealengine.com/t/new-update-causes-uefn-to-crash-on-0-load-every-time/2348684>\
**Category:** Issues and Bug Reporting\
**Tags:** fortnite-creative, unreal-editor-for-fortnite, fortnite\
**Created:** [February 21, 2025, 2:49pm UTC](https://forums.unrealengine.com/t/new-update-causes-uefn-to-crash-on-0-load-every-time/2348684 "2025-02-21T14:49:15Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![NoHoldsBarred](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@NoHoldsBarred](https://forums.unrealengine.com/u/NoHoldsBarred)\
**Post date:** [February 21, 2025, 2:49pm UTC](https://forums.unrealengine.com/t/new-update-causes-uefn-to-crash-on-0-load-every-time/2348684/1 "2025-02-21T14:49:15Z")

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### Summary

I am now unable to open UEFN on my desktop computer after today’s update. I now get the following error:

LoginId:3f6f63d644df302beba75d8997129313  
EpicAccountId:a6d5ee3a547a477797b1d5■■■2148a63

Fatal error: [File:Z:\UEVFS\Root\Engine\Source\Runtime\PakFile\Private\PakFile.cpp] [Line: 370]  
Corrupt pak index detected on pak file: ../../../FortniteGame/Content/Paks/pakChunkEarly-WindowsClient.pak

Any ideas how to fix?

### Please select what you are reporting on:

Unreal Editor for Fortnite

### What Type of Bug are you experiencing?

Stability

### Steps to Reproduce

Try to launch editor, crashes

### Expected Result

Editor shouldn’t crash

### Observed Result

Editor crashes every time I try to open it.

### Platform(s)

PC

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<div class="post-metadata">

**Author:** ![Jimbohalo10](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/jimbohalo10/32/961440_2.png) [@Jimbohalo10](https://forums.unrealengine.com/u/Jimbohalo10)\
**Post date:** [February 21, 2025, 4:05pm UTC](https://forums.unrealengine.com/t/new-update-causes-uefn-to-crash-on-0-load-every-time/2348684/2 "2025-02-21T16:05:37Z")

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hi @NoHoldsBarred ,  
The error is due to part of an update not successfully completed. Part of your update is missing, usually due to a transient network error.

This often happens in Windows 11 make sure you have enough free space on disk first

You will need to verify your UEFN installation as in past post

[How to Verify UEFN](https://forums.unrealengine.com/t/urc-exe-and-urc-dll-get-flagged-as-malware-from-microsoft-defender/1802519/5)

If this does not work try deleting files in Windows File Explorer path

C:\Program Files\Epic Games\Fortnite\FortniteGame\Content\Paks

next of into Epic Launcher as in the link above and try Verify again

If you tried to load in UEFN before 1200 GMT the final pack on my Windows 11 was deleted

If that does not work you will uninstall UEFN and reinstall using the same post picture

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**Author:** ![system](https://d3kjluh73b9h9o.cloudfront.net/original/4X/7/1/3/713c9d3f58553f0de89543d76a8a3a2779dc9fa4.png) [@system](https://forums.unrealengine.com/u/system)\
**Post date:** [August 20, 2025, 2:49pm UTC](https://forums.unrealengine.com/t/new-update-causes-uefn-to-crash-on-0-load-every-time/2348684/3 "2025-08-20T14:49:42Z")

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