Defining Native Application in IIS?

[G00GLER]

There is a way to do this using HTTP header:

http://support.microsoft.com/kb/260519/EN-US/

but I don't understand the example given:
Content-disposition: attachment; filename=fname.ext

SUMMARY
When you serve a document from a Web server, you might want to immediately prompt the user to save the file directly to the user's disk, without opening it in the browser. However, for known MIME (Multipurpose Internet Mail Extensions) types such as Microsoft Word ("application/ms-word"), the default behavior is to open the document in Internet Explorer.

 

[Sheco]

The example assumes the use of a server-side scripting technology such as ASP.