Mysterious URL remapping in ASP.Net
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I'm working on a legacy ASP.Net web forms app that is remapping the sitemap URL.  When I go to www.mysite.com/sitemap.xml it's redirecting to sitemap.aspx.

I don't see anything in the web.config file dealing with URL mapping, so I'm not sure what might be doing this.  I've heard from coworkers not intimately familiar with this particular app that an ISAPI redirection may be in place, but I'm not sure where to look for that, having never dealt with it.  

Would anyone know what to try?  This site is ASP.Net 2.0 running in IIS 7.5.  Thanks much.