HTTP Error 500.31 - ANCM Failed to Find Native Dep

Question

I try to run a Blazor application.

Web.Server runs .NET Core 3.0
Web.Client runs .NET Standard 2.0
Web.Shared runs .NET Standard 2.0

After publishing and uploading the application to IIS i get this error:

HTTP Error 500.31 - ANCM Failed to Find Native Dependencies
Common solutions to this issue:
The specified version of Microsoft.NetCore.App or Microsoft.AspNetCore.App was not found.

Event Viewer contains this error message:

HTTP Error 500.31 - ANCM Failed to Find Native Dependencies

When I run dotnet --info I can see that I both Microsoft.NetCore.App and Microsoft.AspNetCore.App contains version 3: PS C:\Users\FooBar> dotnet --info .NET Core SDK (reflecting any global.json): Version: 3.0.100-preview6-012264 Commit: be3f0c1a03

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.17763
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\3.0.100-preview6-012264\

Host (useful for support):
  Version: 3.0.0-preview6-27804-01
  Commit:  fdf81c6faf

.NET Core SDKs installed:
  1.0.4 [C:\Program Files\dotnet\sdk]
  2.0.0 [C:\Program Files\dotnet\sdk]
  2.1.101 [C:\Program Files\dotnet\sdk]
  3.0.100-preview6-012264 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
  Microsoft.AspNetCore.All 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.0.0-preview6.19307.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 1.0.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 1.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.0.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 2.1.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

To install additional .NET Core runtimes or SDKs:
  https://aka.ms/dotnet-download

ASP.NET Core Diagnostics:

IMPORTANT: This report might contain confidential information. Mask such before sharing to others.
-----
System Time: 6/18/2019 12:50:58 AM
Processor Architecture: AMD64
OS: Microsoft Windows NT 10.0.17763.0
Server Type: IIS

Scan 31 installed module(s).
ASP.NET Core module version 2 is installed for .NET Core 2.2 and above: C:\Program Files\IIS\Asp.Net Core Module\V2\aspnetcorev2.dll (13.0.19158.0).

Scan 86 registered handler(s).
* Found a valid ASP.NET Core handler as { Name: aspNetCore, Path: *, State: Enabled, Module: AspNetCoreModuleV2, Entry Type: Local }.
  Visual C++ runtime is detected (expected: 14.0, detected: 14.14.26405.0 built by: VCTOOLSREL): C:\WINDOWS\system32\msvcp140.dll.
Scan aspNetCore section.
    "processPath": dotnet.
    "arguments": .\Web.Server.dll.
    "hostingModel": inprocess.
"runtimeTarget": .NETCoreApp,Version=v3.0.
Please refer to pages such as https://dotnet.microsoft.com/download/dotnet-core/2.2 to verify that ASP.NET Core version 13.0.19158.0 matches the runtime of the web app.

Why is IIS throwing this error on my server?

Note: It works from Visual Studio 2019.

Answer 1

I have received the same error after upgrading my ASP.NET Core project from .NET Core 3.0 to 3.1 and installing Microsoft .NET Core 3.1.0 - Windows Server Hosting.

Quick (but bad) fix

changed the web.config handler from AspNetCoreModuleV2 to AspNetCoreModule and it worked ok.

Good fix

Find the underlying cause by inspecting Event Viewer. There might be multiple causes for this error, but in my case it was not finding an assembly related to CodeAnalysis

Unable to locate application dependencies. Ensure that the versions of Microsoft.NetCore.App and Microsoft.AspNetCore.App targeted by the application are installed.

Could not find 'aspnetcorev2_inprocess.dll'. Exception message: Error: An assembly specified in the application dependencies manifest (myproject.deps.json) was not found: package: 'Microsoft.CodeAnalysis.CSharp.Workspaces', version: '3.3.1' path: 'lib/netstandard2.0/Microsoft.CodeAnalysis.CSharp.Workspaces.dll'

Although they are related these messages were in different events.

Answer 2

Addition to the answer from @Alexei:

I got this error using a Azure App Service.

Goto https://<your-app>.scm.azurewebsites.net/detectors?type=tools&name=eventviewer or log in to the Azure portal and navigate to "Diagnose and solve problems" to see a better error description.

In my case I had the error:

Could not find 'aspnetcorev2_inprocess.dll'. Exception message: Failed to add 'D:\local\UserProfile.dotnet\tools' to the PATH environment variable. Add this directory to your PATH to use tools installed with 'dotnet tool install'.

I did not recognize aspnetcorev2_inprocess.dll so I decided to check my wwwroot folder to look for clues:

https://<your-app>.scm.azurewebsites.net/DebugConsole/?shell=powershell

Located at D:\home\site\wwwroot in my case. Here I could see a couple of DLLs I did not expect to be there. Turned out that our Azure DevOps Pipeline published our solution instead of web project and we had merged a new Azure Functions project to develop branch. After fixing the publish everything worked.

Useful link for more troubleshooting:

https://docs.microsoft.com/en-us/aspnet/core/test/troubleshoot-azure-iis?view=aspnetcore-3.1

Answer 3

I had the same error message when I deployed from our dev server to our staging server. I fixed the issue by adding the Nuget package Microsoft.NetCore.App (version 2.2.8). Sometimes the answer is in the error message.