[thelist] ASP.NET Security - protect a downloadable document

[Casey]

Okay, I am scratching my head over this one.  If someone can help explain
this to me I would be VERY grateful.

I have a directory configured as an application on the server.  Here's the
entire web.config file:

<configuration>
  <system.web>
      <authentication mode="Forms">
        <forms name=".ASPXUSERDEMO" loginUrl="login.aspx" protection="All"
timeout="5" />
      </authentication>
      <authorization>
        <deny users="?" />
      </authorization>
    <globalization requestEncoding="UTF-8" responseEncoding="UTF-8" />
 <compilation debug="true"/>
 <customErrors mode="Off"/>
  </system.web>
</configuration>

This seems to work fine for requesting .aspx pages, but what the client is
trying to secure is a powerpoint presentation.  When linking to it, it
allows the download rergardless of the login status of the user.

How then would I protect such files?

Thanks!!!