Failed to load the hostfxr.dll after install net core

Question

Anyone has this problem i change Pc and tried to install net core framework but vs code return this info when i tried to write dontet --info

Failed to load the dll from [C:\Program 
Files\dotnet\host\fxr\2.1.0\hostfxr.dll], HRESULT: 0x80070057
The library hostfxr.dll was found, but loading it from C:\Program 
Files\dotnet\host\fxr\2.1.0\hostfxr.dll failed
- Installing .NET Core prerequisites might help resolve this problem.
 http://go.microsoft.com/fwlink/?LinkID=798306&clcid=0x409

Solution 1

TL;DR Since the original download is no more, here's what I found on the dell forums:

Standalone package: Microsoft Update Catalog - KB4457144

I had the exact same error message (apart from the directories) on Win7 with a newer VC++ redist already present.

The package contains the KB2533623 that we want. Details of KB4457144: September 11, 2018—KB4457144 (Monthly Rollup)

After installation and a reboot, dotnet new console goes through without an error.

Dell forum source: Microsoft Windows 7 Update KB2533623 needed to install Dell Update Package (DUP)

Solution 2

I faced the same error and I checked my Web API Program.cs class and found that: .UseIISIntegration() is missing. I added it and the problem solved.

public class Program
{
    public static void Main(string[] args)
    {
        CreateWebHostBuilder(args).Build().Run();
    }

    public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
        WebHost.CreateDefaultBuilder(args).UseStartup<Startup>().UseIISIntegration();
}

Comments

[Uwe Keim]

For in-process, this should be .UseIIS() instead of .UseIISIntegration().

[H.A.H.]

Just wanna tell you, that if you and others like you did not exist, I would have become MAC user long ago. Saved me my Sunday night...

[Xan-Kun Clark-Davis]

Glad I could help. Took me a good while to hunt this file down and wanted to make sure, I can save someone else the hassle :-)