Web Api Returning 4040

Question

I am getting a 404 from a .net core 5.0 web app that I have deployed to a newly set up windows server.

I have installed the dotnet-hosting-5.0.11-win runtime libraries on the server and installed IIS with the following settings:

When I browse to it from IIS I get a 404. I gave up on the initial project and started clean with a stripped down version from the VS2019 templates. Still got the 404 :

404 Error

Here is the project from VS2019 itself just to give you a clearer idea of what I am trying to install and run from the Windows server:

Here are the publish options for the project:

Created a new website in IIS for this app. Here are the settings for that:

Here are the app pool settings for the app:

Here is the web.config file for the app:

Enabled directory browsing based on other posts I read:

Here is a snapshot of the logs file on the server:

Any help appreciated!

Answer 1

Hi @Rezwan Khan ,

I have reproduced the issue. It was caused by this code in startup file.

if (env.IsDevelopment())  
            {  
                app.UseDeveloperExceptionPage();  
                app.UseSwagger();  
                app.UseSwaggerUI(c => c.SwaggerEndpoint("/swagger/v1/swagger.json", "WebApplication1 v1"));  
            }  

It only works when environment is development. So you need to add this in web.config.

 <environmentVariables>  
    <environmentVariable name="ASPNETCORE_ENVIRONMENT" value="Development" />  
  </environmentVariables>  

The full element structure is

<aspNetCore processPath="dotnet" arguments=".\TestWebApi.dll" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" hostingModel="inprocess">  
 <environmentVariables>  
    <environmentVariable name="ASPNETCORE_ENVIRONMENT" value="Development" />  
  </environmentVariables>  
</aspNetCore>  

Then you can access it well.

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Best regards,
Bruce Zhang