Unable to view detailed errors

[Fredoid]

Hi,
I am running classic ASP.Net MVC application with .Net Framework 4.0 into an aspnet:latest docker container. Website seems to work fine into the container because I can navigate into it.

Sometimes the application raises errors and exceptions but I can't view them. My browser display the standard iis error The page cannot be displayed because an internal server error has occurred in a white page .

I've tried those following solutions in my web.config

• system.web/customError mode="Off"
• system.webServer/httpErrors errorMode="Detailed" and existingResponse="PassThrough"
• system.webServer/asp appAllowClientDebug=true and scriptErrorSentToBrowser=true

I have olso tested unlocking IIS Feature Delegation

c:\Windows\system32\inetsrv\appcmd unlock config –section:httpErrors
c:\Windows\system32\inetsrv\appcmd unlock config -section:system.webServer/asp
c:\Windows\system32\inetsrv\appcmd unlock config -section:system.webServer/httpErrors
c:\Windows\system32\inetsrv\appcmd unlock config -section:system.web/customErrors

Nothing change, same issue, The page cannot be displayed because an internal server error has occurred.

For information, with PS Get-EventLog I can see real exception with stack trace and full of information, but my problem is that I would like to view errors details directly in my browser as I always worked with VS and IIS.

No more idea on my side, and you ?

Thanks,
Fred

[shirhatti]

By default on IIS you only see detailed error pages on localhost. You can enable detailed error pages for all remote clients by setting this in your web.config. Just be careful not to enable this in production as you'll be leaking implementation details

<configuration>
  <system.webServer>
    <httpErrors errorMode="Detailed" />
  </system.webServer>
</configuration>