HttpError iis config throws exception when default path is added

Question

I have this config which works and redirects the following errors correctly

<httpErrors errorMode="Custom" 
        existingResponse="Replace" 
        defaultResponseMode="ExecuteURL" >
  <remove statusCode="403" />
  <remove statusCode="404" />
  <remove statusCode="500" />
  <error statusCode="403" responseMode="ExecuteURL" path="/Error/AccessDenied" />
  <error statusCode="404" responseMode="ExecuteURL" path="/Error/PageNotFound" />
  <error statusCode="500" responseMode="ExecuteURL" path="/Error/ApplicationError" />
</httpErrors>

But when I add the following default path to try to add a catch all

<httpErrors errorMode="Custom" 
        existingResponse="Replace" 
        defaultResponseMode="ExecuteURL" 
        defaultPath="/Error/ApplicationError">

The server throws a web.config error

HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.
Module     CustomErrorModule

Now this directly contradicts the documentation on msdn

Any help would be greatly appreciated!!

Answer 1

You cannot override httpErrors "defaultPath" attribute in IISExpress because of applicationhost.config locked that attribute:

<httpErrors lockAttributes="allowAbsolutePathsWhenDelegated,defaultPath">

You can read more about it here: https://support.microsoft.com/en-us/kb/942055 This problem can occur:

when the specified portion of the IIS configuration file is locked at a higher configuration level. To resolve this problem, unlock the specified section, or do not use it at that level. For more information on configuration locking, see How to Use Locking in IIS 7.0 Configuration.