What It Means & How to Fix It in UE5

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🧠 Why You’re Seeing This Error

This error means Unreal Engine can’t find a valid precompiled header (PCH) for one of your modules.

Every UE5 module is expected to either:

• Use a shared or explicit PCH, or
• Disable PCH entirely (less common)

If your module doesn’t have a designated PCH — or if it points to a file that doesn’t exist — you’ll get this error during compilation.

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💥 Example Error Message

UnrealBuildTool: ERROR: Module 'MyModule' is missing a PCH header file. Please add a header file to be used as your PCH.

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🛠️ What Usually Causes This

❌ You Didn’t Define a PCH in Your .Build.cs

// No PCHUsage setting defined

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❌ You Set a PCH File That Doesn’t Exist

PrivatePCHHeaderFile = "Private/MyModule.h"; // ❌ File doesn't exist

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❌ Your Module Has No Central Header File

Even if you don’t specify one, Unreal expects a convention-based header like:

MyModule/Public/MyModule.h

Or:

MyModule/Private/MyModulePrivatePCH.h

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✅ How to Fix It – Step-by-Step

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✔️ 1. Create a PCH Header File

You can call it anything, but typically:

// File: MyModule/Private/MyModule.h

#pragma once

#include "CoreMinimal.h"

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✔️ 2. Reference It in Your .Build.cs File

Add this to your module’s .Build.cs:

PCHUsage = PCHUsageMode.UseExplicitOrSharedPCHs;
PrivatePCHHeaderFile = "Private/MyModule.h";

Make sure the path is relative to the module root, and the file actually exists.

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✔️ 3. Optional – Use Shared PCH Mode (Simpler, Less Explicit)

If you don’t want to create your own PCH file:

PCHUsage = PCHUsageMode.UseSharedPCHs;

This tells Unreal to just use its default (CoreMinimal.h) for this module.

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✔️ 4. Rebuild After Adding PCH Setup

After updating the .Build.cs, do a clean rebuild:

- Right-click .uproject → Generate Visual Studio project files
- Delete Intermediate/ if needed
- Rebuild from scratch

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✅ Summary: How to Fix “Module Is Missing a PCH Header File” in UE5

Cause	Fix
No PCH file set in .Build.cs	Add PrivatePCHHeaderFile = "..." and a matching file
Incorrect path or file name	Confirm the file exists at the correct relative location
No PCH usage setting at all	Set PCHUsage = PCHUsageMode.UseExplicitOrSharedPCHs;
Want to skip custom PCH	Use PCHUsage = PCHUsageMode.UseSharedPCHs;