ASP.NET Identity - protecting a directory from unauthenticated users - asp.net

Question

I am using ASP.NET 4.5 OWIN Identity and attempting to block access to a directory for all but authenticated users. The directory contains raw files, so it isnt possible to wrap them in the ASP LoggedInTemplate tag.
When I try and prevent access to the directory to anonymous users, it fails.
I have tried adding the following to the main Web.config file:
<system.web>
<authorization>
<deny users="?" />
</authorization>
</system.web>
<location path="/docs">
<system.web>
<authorization>
<deny users="?" />
</authorization>
</system.web>
</location>
Doing this gives server 500 errors and highlight the location path="/docs" line as the source of the error. This is a hosted solution, so options for changing the IIS server config to allow overrides arent available to me, though that does seem one potential solution for anyone experiencing this issue.
I have now removed the above from the main web.config and added a separate web.config file in the directory that I want to protect. The new web.config contains this:
<?xml version="1.0"?>
<configuration>
<system.web>
<authorization>
<deny users="?" />
</authorization>
</system.web>
</configuration>
This gives no errors, but allows unauthenticated users access to the folder, which is what I am trying to prevent.
Any ideas or pointers to any article that describes how to resolve this would be much appreciated.

Answer 1

The solution to this for my environment was to use the web.config file in the sub directory, but to add a custom handler definition for the file types in question.
<?xml version="1.0"?>
<configuration>
<system.web>
<authorization>
<deny users="?" />
</authorization>
</system.web>
<system.webServer>
<handlers>
<add name="PDFHandler" verb="*"
path="*.pdf"
type="System.Web.StaticFileHandler"
resourceType="Unspecified" />
</handlers>
</system.webServer>
</configuration>
The web server then allows authenticated users only to access the files in the sub directory.
This article led my to the solution: http://www.primaryobjects.com/CMS/Article112