LowLevelFatalError [File:E:\M2\1.00.10\BigCat_UE_Source\Engine\Source\Runtime\Engine\Private\ShaderCompiler\ShaderCompiler.cpp] [Line: 4578] Missing global shader FFXFIAdditionalUICS's permutation 0, Please make sure cooking was successful.

I’m trying to apply a mod to an Unreal Engine 5.5 game, but I keep getting the following error. Is there any way to fix it?

LowLevelFatalError [File:E:\M2\1.00.10\BigCat_UE_Source\Engine\Source\Runtime\Engine\Private\ShaderCompiler\ShaderCompiler.cpp] [Line: 4578]
Missing global shader FFXFIAdditionalUICS’s permutation 0, Please make sure cooking was successful.

0x00007ff6ecb13423 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ecb15279 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ece4ba32 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ece4e959 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ece42a84 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ece57e1a BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ece58b45 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6ece58c3b BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ff6f0fa7216 BigCat-Win64-Shipping.exe!UnknownFunction
0x00007ffb7f77e8d7 KERNEL32.DLL!UnknownFunction

Hello there @_21167!

I think the key line in your log is “Missing global shader FFXFIAdditionalUICS’s permutation 0, Please make sure cooking was successful.” That shader reference is aiming at the exact elements causing the crash:

  • FFX refers to AMD’s FidelityFX SDK
  • FI is Frame Interpolation, part of the same plugin package
  • AdditionalUiCSS is the UI composition pass, used for blending the HUD on top of the generated frames

Meaning, the crash is not being caused by an element inside the game. Rather, it’s related to the AMD plugins. The Frame Interpolation module is failing to get its global shaders included in the build, and when the engine checks the shader cache, the whole thing crashes.

So, in order to fix the problem, you can check for any available updates for the plugin, or disable it temporarily for the build process. After taking either of these actions, please fully clear the shader cache. To do so, navigate to the game’s main directory, and delete folders DerivedDataCache, Intermediate, and Saved, then test again.