Unreal Engine 5 Early Access 101

Solutions to common bugs and problems with Unreal Engine 5, centered in one place.

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This content is relevant to Unreal Engine 5

Unreal Engine 5 Early Access 101

This page contains solutions to common bugs and problems with Unreal Engine 5, centered in one place.

Creating a cpp Project Missing hostfxr.dll

When one creates a new cpp project in Unreal Engine 5 Early Access, the following error appears: 1

An error occurred while trying to generate project files.

Running .../Epic Games/UE_5.0EA/Engine/Binaries/DotNET/UnrealBuildTool/UnrealBuildTool.exe  -projectfiles -project="..." -game -rocket -progress
A fatal error occurred. The required library hostfxr.dll could not be found.
If this is a self-contained application, that library should exist in [...\Epic Games\UE_5.0EA\Engine\Binaries\DotNET\UnrealBuildTool\].
If this is a framework-dependent application, install the runtime in the global location [C:\Program Files\dotnet] or use the DOTNET_ROOT environment variable to specify the runtime location or register the runtime location in [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x64\InstallLocation].

The .NET Core runtime can be found at:
  - https://aka.ms/dotnet-core-applaunch?missing_runtime=true&arch=x64&rid=win10-x64

This caused from Unreal Engine 5 expecting to have a .NET framework of version 3.10 for some reason. You can download and install it from the following link, then the problem should be solved:

Download .NET Core 3.1 SDK (v3.1.409) - Windows x64 Installer

References

Footnotes

  1. Missing hostfxr.dll (.NET Core Runtime) When Creating a UE5 Project | Unreal Engine Forums