Deploying website: 500 - Internal server error

Question

First, you need to enable and see detailed errors of your web messages, because this is a general message without giving information on what's really happening for security reasons.

With the detailed error, you can locate the real issue here.

Also, if you can run the browser on the server, you get details on the error, because the server recognizes that you are local and shows it to you. Or if you can read the log of the server using the Event Viewer, you also see the details of your error.

On IIS 6

<configuration>
    <system.web>
        <customErrors mode="Off"/>
        <compilation debug="true"/>
    </system.web>
</configuration>

On IIS 7

<configuration>
    <system.webServer>
        <httpErrors errorMode="Detailed" />
        <asp scriptErrorSentToBrowser="true"/>
    </system.webServer>
    <system.web>
        <customErrors mode="Off"/>
        <compilation debug="true"/>
    </system.web>
</configuration>

Note: You can avoid the Debug=true. You only need to close the custom errors for a while and get the detailed error page.

Reference: Enabling Windows custom error messaging in Go Daddy's help articles.

Also, this can help: How to enable the detailed error messages (from IIS).

I was pulling my hair out over this issue. Making sure the following entry was in the root web.config file fixed it for me:

<configuration>
  <system.webServer>
    <validation validateIntegratedModeConfiguration="false" />
  </system.webServer>
</configuration>

Remember that you have to add this to the existing XML elements, if they're already there. You can't just add at the end of the file, because you can't have multiple copies of any element.

For me, the following code in the web.config was the culprit. When I removed it, the web site worked fine.

  <staticContent>
    <mimeMap fileExtension=".mp4" mimeType="video/mp4" />
  </staticContent>

I finally solved this "500 Internal server" error when deploying the ASP.NET MVC 3.0 application on godaddy.ocm shared hosting.

somehow there were discrepancies on the version of DLL files referenced and version mentioned in file web.config.

I tried all the options mentioned in various forum. Nothing helped, although everyone suggested the same kind of fix, but somehow it didn't work in my scenario. Finally after banging my head for two days. I decided to delete all DLL file reference and delete web.cofig (make a local copy) from the project and let the application throw the error and then add the DLL files one by one making copy to local=true.

After all the DLL files were added, I created a new ASP.NET MVC application and copied the web.config of new application to my actual application. So my actual application now has a new web.config, and then I copied the connectionstring and other references from the local copy of web.config that I saved.

I just compiled the application and published to a local folder and FTP the published folder to goDaddy.

It worked and finally my problem was solved.

In my case, I put a mistake in my web.config file. The application key somehow was put under the <appSettings> tag. But I wonder why it doesn't display a configuration error. The error 500 is too generic for investigating the problem.