Clair Obscur Expedition 33 Fatal Error UE-Sandfall Crash Fix on PC

What is the UE-Sandfall Fatal Error in Clair Obscur: Expedition 33?

The UE-Sandfall fatal error is a crash that occurs in Clair Obscur: Expedition 33, the Unreal Engine 5 RPG developed by Sandfall Interactive (Montpellier, France). When the game crashes, players see a dialog reading "Fatal error! The UE-Sandfall Game has crashed and will close." Some players also encounter a LowLevelFatalError at launch, or a shader decompression crash: DecompressShaderWithOodleAndExtraLogging(): Could not decompress shader group with Oodle.

This error has affected players since the game's release on April 24, 2025, across Steam, Epic Games Store, and Xbox Game Pass on PC. As of patch 1.5.1 (December 2025), many crash triggers have been fixed, but DirectX 12 and driver conflicts persist.

When does it occur?

• At startup, right after the initial benchmark prompt
• During loading screens between areas or when loading a save file
• Mid-battle or during cutscenes with heavy visual effects
• After updating GPU drivers without clearing shader cache
• When Steam Overlay is enabled (pre-patch 1.5.0)
• On Intel 13th/14th Gen CPUs with known instability issues

Common causes

• DirectX 12 incompatibility — the game defaults to DX12 via UE5, which crashes on many GPU/driver combinations
• Corrupted shader cache — old Sandfall_PCD3D_SM6.upipelinecache files persist after driver updates
• Steam Overlay conflict — the rendering overlay conflicts with UE5 (fixed in patch 1.5.0 but still affects some setups)
• NVIDIA driver 576.28 — this specific driver version causes random gameplay crashes
• Factory GPU overclocks — AIB GPUs (ASUS, MSI, etc.) running above reference clocks trigger UE5 instability
• Unlocked frame rate — uncapped FPS causes GPU/CPU load spikes
• Overlay software — Discord, GeForce Experience, MSI Afterburner, or RGB software conflicting with UE5 rendering

Step-by-step fixes

1. Force DirectX 11 — Right-click the game in Steam > Properties > Launch Options > type -dx11. This is the single most effective fix. Alternatively, navigate to Steam\steamapps\common\Expedition 33\Sandfall\Binaries\Win64\ and delete D3D12.dll (back it up first).

1. Clear the shader cache — Navigate to %LOCALAPPDATA%\Sandfall\Saved\ and delete the file Sandfall_PCD3D_SM6.upipelinecache. Back up the SaveGames subfolder first. The game will recompile shaders on next launch (longer initial load is normal).

1. Disable Steam Overlay — Right-click the game in Steam > Properties > General > uncheck "Enable the Steam Overlay while in-game". Also disable overlays in Discord (Settings > Game Overlay), GeForce Experience, and MSI Afterburner.

1. Update or roll back GPU drivers — For NVIDIA, avoid driver 576.28. Install the latest stable driver or roll back to 566.36 (last confirmed fully stable version). Use DDU (Display Driver Uninstaller) in Safe Mode for a clean install. Always clear the shader cache after changing drivers.

1. Disable GPU overclocks — For NVIDIA: open NVIDIA Control Panel > Help > Enable Debug Mode (forces reference clocks). For AMD: open Adrenalin > Performance > Tuning > reduce Maximum Frequency incrementally.

1. Cap your frame rate — Enable VSync in the game's graphics settings or set the in-game Max FPS limiter to 60. This prevents GPU/CPU load spikes that trigger UE5 crashes.

1. Verify game files — Right-click the game in Steam > Properties > Installed Files > "Verify integrity of game files".

1. Run as administrator — Navigate to Sandfall\Binaries\Win64\, right-click SandFall-Win64-Shipping.exe > Properties > Compatibility > check "Run this program as an administrator".

If it still doesn't work

If crashes persist, check for Intel 13th/14th Gen CPU instability — download Intel Extreme Tuning Utility (Intel XTU) and lower the Performance Core ratio to 50x, then test for stability. Apply Intel's official microcode update via your motherboard's latest BIOS.

For the specific Oodle shader decompression crash, delete the entire %LOCALAPPDATA%\Sandfall\Saved\ folder (keeping only your SaveGames backup), then verify game files through Steam. If you're on Game Pass, saves are at %LOCALAPPDATA%\Packages\KeplerInteractive.Expedition33_ymj30pw7xe604\SystemAppData\wgs\. Report persistent crashes on the [Steam Community](https://steamcommunity.com/app/1903340/discussions/) or the [Sandfall Interactive Discord](https://discord.gg/sandfall) with your crash logs from %LOCALAPPDATA%\Sandfall\Saved\Logs\.