What It Means & How to Fix It in UE5 C++
🧠 Why You’re Seeing This Error
LNK2022 is a linker error caused by a metadata failure, usually from .NET interop, C++/CLI, or other managed/unmanaged code mix-ups.
In a UE5 project, this almost always means:
- You’re integrating a C++/CLI (.NET) library or plugin
- You’ve mixed /clr (managed) and native UE5 modules
- A metadata token or method signature can’t be resolved during the link phase
💥 Example Error Message
LNK2022: metadata operation failed (8013118D) : CustomAttribute: token (0x0A00001F) is not a valid MemberRef
🛠️ Example Scenario (UE5 + .NET)
You’ve added a managed .NET wrapper to your UE5 project and call a function from it, but:
- The .dll or metadata file is missing
- The function’s attribute/signature is malformed
- The method being referenced is marked incorrectly (e.g., internal, missing visibility)
✅ How to Fix LNK2022 in UE5 – Step-by-Step
✔️ 1. Avoid /clr in Game Modules
UE5 is a native C++ engine. If you need to use .NET:
- Wrap it in a separate interop module or DLL
- Avoid using
/clrin your main game or plugin modules
✔️ 2. Check That All .NET DLLs Are Referenced Properly
- Ensure all managed assemblies are available during link time
- If you’re consuming
.NETcode through C++/CLI, make sure it’s built for the correct platform (x64)
✔️ 3. Recompile Any C++/CLI Assemblies
Metadata errors like this can result from:
- Binary incompatibility (UE5 expects x64, but you linked x86)
- Assembly mismatch
- Mismatched CLR version between your build and UE5 (which doesn’t use CLR at all)
✔️ 4. Use P/Invoke or COM Instead of Mixing /clr in UE5
If you need to use managed code, prefer runtime interop over static linking:
- Use
DllImportin C# - Use
LoadLibraryandGetProcAddressin C++
Keep .NET code out of the UE5 module build pipeline.
✅ Summary: How to Fix LNK2022 in UE5
| Cause | Fix Example |
|---|---|
Using /clr in UE5 module | Avoid it — separate managed code into external DLL |
| Metadata mismatch between assemblies | Rebuild .NET assemblies using the correct architecture (x64) |
Incomplete or missing .NET reference | Ensure DLLs are linked and attributes are valid |
| Mixed .NET/C++/UE5 compilation pipeline | Use P/Invoke or COM interop instead of direct linking |
