Can't open UE5 demo - "The required library hostfxr.dll could not be found"

Hi all,
First, I got a message that the demo level couldn’t be opened with the current version of UE, so it made a copy…

However, I’m unable to open the copy, as it still wants to duplicate it, and I get this error:

Project files could not be generated. Log output:

Running E:/UE_4.23/UE_5.0EA/Engine/Binaries/DotNET/UnrealBuildTool/UnrealBuildTool.exe -projectfiles -project=“F:/Unreal Engine Projects/UE5 Demo/ValleyoftheAncient 5.0 - 2/AncientGame.uproject” -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 [E:\UE_4.23\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:


No idea how to fix this.

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I get a similar error for my own project updating from UE4.26.1.

But I only have Visual Studio 2017 installed and I guess installing the “dotnet core” should fix it ( or it is automatically fixed if you install VS2019+ ).

Actually, when I installed UE5 it also installed the Visual Studio update. Hm…

It only installed the Engine and I noticed it installed Quixel Bridge.

When I create new first person blueprint project and hit the Play button it crashes:

Assertion failed: ClearValue.ColorBinding == EClearBinding::EColorBound [File:D:/build/++UE5/Sync/Engine/Source/Runtime/Windows/D3D11RHI/Private/D3D11Commands.cpp] [Line: 1129] Texture: MotionBlur.SceneColor does not have a color bound for fast clears

UnrealEditor_D3D11RHI
UnrealEditor_D3D11RHI
UnrealEditor_RenderCore
UnrealEditor_RenderCore
UnrealEditor_RenderCore
UnrealEditor_Renderer
UnrealEditor_Renderer
UnrealEditor_Renderer
UnrealEditor_Renderer
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_Core
UnrealEditor_RenderCore
UnrealEditor_RenderCore
UnrealEditor_Core
UnrealEditor_Core
kernel32
ntdll

When I use the menu bar → Platforms → Quick Launch → Desktop Windows XYZ I get the following “Verifying the SDK and Device failed” error:


: Verifying SDK and Device (Windows): Running AutomationTool…
UATHelper: Verifying SDK and Device (Windows): A fatal error occurred. The required library hostfxr.dll could not be found.
UATHelper: Verifying SDK and Device (Windows): If this is a self-contained application, that library should exist in [C:\UnrealEngine\UE_5.0EA\Engine\Binaries\DotNET\AutomationTool].
UATHelper: Verifying SDK and Device (Windows): 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].
UATHelper: Verifying SDK and Device (Windows): The .NET Core runtime can be found at:
UATHelper: Verifying SDK and Device (Windows): - .NET Downloads (Linux, macOS, and Windows)
UATHelper: Verifying SDK and Device (Windows): BUILD FAILED
LogSlate: Window ‘SDK Verification’ being destroyed
Took 0.000200 seconds to synchronously load lazily loaded font ‘…/…/…/Engine/Content/Editor/Slate/Fonts/FontAwesome.ttf’ (139K)

I had this same problem. The fix is to download and install DotNET 3.1 … the hosting bundle worked for me without an issue … Download .NET Core 3.1 (Linux, macOS, and Windows)

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Thanks, will try it out.

This fixed the issue. Thanks

Installing dotnet 3.1 worked, thank you very much my good man.

Nope. I would not like to “rebuild” them. AGAIN.

missing-modules

Tried opening a small existing project. Stuck at 3,141 shaders & completely locked up my machine. There’s some notice in the lower right, but I can’t read it because it’s covered by the 70% off Unreal Marketplace ad.

Hard reset time.

I don’t know if I’m the only one experiencing this problem but I have been trying to download this for over an hour now …not working .
Can someone please upload the file somehow we can download
Thanks in Advance

Download hostfxr.dll https://cn.dll-files.com/hostfxr.dll.html and move it to floder UE_5.0EA\Engine\Binaries\DotNET\UnrealBuildTool can help!

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thanks your help,it’s worked

Thank you!

I can confirm I got this issue installing the recommended .net framework worked for me. It seems to be tied to C++ projects. I was able to use the engine without any issues until I created an empty C++ project. Not sure if that helps out any at all.

I’m not sure if this helps but there is some C# code in the Visual studio code (projectname).Target.cs, (projectname)Editor.Target.cs, ETC. So this is most likely the requirement for the .net framework.

I am also getting the error about missing hostfxr.dll. In my case, I already had started that project successfully some time ago. Now I wanted to revisit this and it fails.
So I believe, that Windows Updates might possibly be the culprit as well, because I did not change anything else…

Yep, about 2 days ago something got messed up, I didnt change anything either.

Must include .NET SDK in Visual Studio Installer modifiers

This happened to me when i moved a project to another location. Installing Download .NET Core 3.1 Runtime fixed it.

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