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jittdev
jittdev
New Participant
November 29, 2023

Meta Quest/Oculus Unreal from source .NET hostfxr.dll problem Windows 10 Pro

  • November 29, 2023
  • 5 replies
  • 2262 views

Hello everyone. I can't seem to get past this .Net problem when running setup.bat from the
Meta/Oculus fork (github)(most recent 5.3):

Failed to load the dll from [E:\MetaQuestDEV\UnrealEngine\Engine\Binaries\DotNET\GitDependencies\win-x64\hostfxr.dll], HRESULT: 0x80070005
The library hostfxr.dll was found, but loading it from E:\MetaQuestDEV\UnrealEngine\Engine\Binaries\DotNET\GitDependencies\win-x64\hostfxr.dll failed
- Installing .NET prerequisites might help resolve this problem.
https://go.microsoft.com/fwlink/?linkid=798306


I've reinstalled all the .Net 8 dependencies, have 4.8 framework. The hostfxr.dll file IS in the directory it fails to load it from. Just have no clue at this point. Just beginning meta programming so any feedback would be greatly appreciated. Thanks in advance.

    This topic has been closed for replies.

    5 replies

    kenancave
    New Participant
    January 11, 2024

    I have the same issue at tag oculus-5.3.0-release-1.92.0-v60.0

    Official Unreal Engine compiles without issues.

    DotNet info:

    > dotnet.exe --info
.NET SDK:
 Version:           8.0.101
 Commit:            6eceda187b
 Workload version:  8.0.100-manifests.825c015e

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.22621
 OS Platform: Windows
 RID:         win-x64
 Base Path:   C:\Program Files\dotnet\sdk\8.0.101\

.NET workloads installed:
 Workload version: 8.0.100-manifests.825c015e
There are no installed workloads to display.

Host:
  Version:      8.0.1
  Architecture: x64
  Commit:       bf5e279d92

.NET SDKs installed:
  8.0.101 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.App 6.0.26 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 8.0.1 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 6.0.26 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 8.0.1 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 6.0.26 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 8.0.1 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
  x86   [C:\Program Files (x86)\dotnet]
    registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
  Not set

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

     

    kenancave
    New Participant
    January 15, 2024

    I have opened an issue for it in GitHub:

    https://github.com/Oculus-VR/UnrealEngine/issues/378

     

    jittdev
    jittdevAuthor
    New Participant
    January 15, 2024

    hi kenan_cave . i don't want to give you a half answer here but the simple fact is i forgot about this post -- and thus did not update it. i cannot remember the specifics BUT we got it working after: [1] ensuring we updated VS Code to a supported version, [2] included the specific dependencies in VS Code (the most important we were missing were the correct Android Studio dependencies (i think we didn't have NDK 25.1 checked and it has to be Command Line Tools SDK 8.0) per

    https://dev.epicgames.com/community/learning/tutorials/oMMe/unreal-engine-meta-quest-sdk-ndk-jdk-for-the-oculus-5-3-fork-of-the-engine-source

    and also ensure you have the correct libraries for VS Code per

    https://docs.unrealengine.com/5.2/en-US/setting-up-visual-studio-development-environment-for-cplusplus-projects-in-unreal-engine/

    With that I think that's all we did to get it working. I remember we did also copy hostfxr.dll from the standard Unreal 5.2 build over to the same directory location in the Oculus fork tree, but I don't think this did anything (but mentioning it just in case). I truly hope this helps and wish I could be more specific, but we got it working withing a day of this post and then plowed forward instead of return to this.

    kenancave
    New Participant
    January 16, 2024

    Hello jittdev,

    Mine was a permission issue. The dll's were missing the user executable permissions. Now it runs fine.

      jcworsley
      jcworsley
      New Participant
      May 1, 2025

      Thank you, 100% this. For folks who use command line tools to unzip this might be more prevalent, I ran into this after using 7z in a cygwin Terminal. chmod a+x Engine/Binaries/DotNET/GitDependencies/win-x64/*.dll resolved it.

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