Fatal Error opening UEFN Project

[Cleverlike_Studios]

Summary

When opening a project in UEFN v31.30 the engine crashes. This crash did not occur in UEFN v31.20

Fatal error: [File:D:\build++Fortnite\Sync\Engine\Source\Runtime\RenderCore\Private\ShaderParameters.cpp] [Line: 26] Failure to bind non-optional shader resource parameter OutTarget0! The parameter is either not present in the shader, or the shader compiler optimized it out.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Engine Crash

Steps to Reproduce

Open Project. See attached video

Expected Result

Project will not crash the engine when trying to open it.

Observed Result

Engine crashes when trying to open the project.

Platform(s)

PC

Island Code

0909-1879-4957

Additional Notes

Crash Logs
UECC-Windows-6689E0044154D4740F5CCEBEF23EA024_0000.zip (277.0 KB)

[Jimbohalo10]

hi @Cleverlike_Studios
Your error log contains

Guid format shader working directory is -4 characters bigger than the processId version (C:/Users/yourName/AppData/Local/UnrealEditorFortnite/Intermediate/Shaders/WorkingDirectory/30488/).

This shows the corrupted shader area which is NOT cleared by verifying your UEFN installation.

There are lots of leftover files from the earlier UEFN versions.

This was solved in the post
31.20 [Solved] UEFN Fix Validation Error pop up wont “Run” - General / Issues and Bug Reporting - Epic Developer Community Forums (unrealengine.com)

This clears the areas programmatically

[Cleverlike_Studios]

Thanx for getting back to me on this. I’ve tried this yesterday, and the .bat deleted only what was in the downloads folder (where I saved the “UEFNfixRun2.txt” file). Note: I did change the file paths in the UEFNfixRun2.txt to match the user name, as running it without changing the user name gave the error that the path did not exist.

So my next step was to

• Close UEFN
• Manually delete the “intermediate” folder
• Restart UEFN
• Reopen the project in question

This process did not fix the issue.

Would you suggest also deleting the “Saved” folder?

Thanx for you assistance and help

-Ian

[Cleverlike_Studios]

Checking back in with this. Any progress or suggestions?

[Jimbohalo10]

hi @Cleverlike_Studios
Working on a similar problem

[2024.10.18-02.34.52:241][ 0]LogShaderCompilers: Display: Compiling shader autogen file: C:/Users/jxxx/AppData/Local/UnrealEditorFortnite/Intermediate/ShaderAutogen/PCD3D_SM5/AutogenShaderHeaders.ush
The Shader settings are wrong yours is PCD3D_SM6

[2024.10.09-16.12.47:884][ 0]LogShaderCompilers: Display: Compiling shader autogen file: C:/Users/ixxx/AppData/Local/UnrealEditorFortnite/Intermediate/ShaderAutogen/PCD3D_SM6/AutogenShaderHeaders.ush

First, try the easier shortcut to UEFN and add DX11 as an Additional Parameter

in this picture, copy and paste the line below we need to add Dx11 and sm5
to give -d3d11 -sm5 at the end of Target box

"C:\Program Files\Epic Games\Fortnite\FortniteGame\Binaries\Win64\UnrealEditorFortnite-Win64-Shipping.exe" -d3d11 -sm5

Now start UEFN from the Desktop Shortcut

Update remove the highly technical text as of 32.00 the control file .ini no longer exista

[Cleverlike_Studios]

Thank you for getting back to me. I will try this and get back to you.

[Cleverlike_Studios]

That worked. Thanx for the assist. Here is a quick TL;DR tutorial to address this issue.

[Fallen-Champ]

@Jimbohalo10

-d3d11 -sm5

Will have another go at doing this tomorrow, found the location but must have done it wrong

Thanks for the info

That above was after adding -d3d11 -sm5

This was the original issue - I am back to this now

[Jimbohalo10]

hi @Fallen-Champ ,
Please refer to the new thread
[Solved] How to fix Fatal Errors in UEFN related to Graphic Cards and Shaders and Derived Data problems