I'm running into a specific issue with my web.config when trying to serve XML files.
As soon as I add this rule:
<add name="XmlFile" path="*.xml" verb="GET,HEAD"
modules="StaticFileModule" resourceType="File" />
I only get an error when I navigate to Index.aspx:
Cannot add duplicate collection entry of type 'add' with unique key attribute 'name' set to 'XmlFile'
If I delete the line or try this:
<remove name="XmlFile" />
then Index.aspx stops working and I get:
Server Error in '/Index.aspx' Application.
The resource cannot be found.
Requested URL: /Index.aspx
Everything else works. Only Index.aspx fails, and only when I touch this XML handler rule.
Environment:
- ASP.NET WebForms written in VB.NET
- .NET Framework 4.7.2
I need XML to be accessible but the rule shouldn't break the default page.
What is causing the duplicate-rule conflict, and why does removing it trigger a 404 specifically for Index.aspx?