Debugging WPF browser applications gives a download file

I have built an application for my college work in WPF browser, but when I try to debug, Firefox opens and gives me a download of the xbap file, which should run in the browser. This happens in VS2008 Express and VS2010 beta. I have tried in Internet Explorer and Chrome with the same result. .NET is framework is inst开发者_如何转开发alled right upto v4.0. This didnt happen before I started using Windows 7, but this shouldn't make much difference, right? Any ideas? Thanks

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Check your MIME type settings in IIS. In earlier versions of Windows this was somewhat obscure to find in the UI, but in 7 it's easy: Start -> search for IIS -> choose IIS Manager -> filter for MIME.

You need to have the following types configured:

MIME Type                        Extension
application/manifest             .manifest
application/x-ms-xbap            .xbap
application/octet-stream         .deploy
application/x-ms-application     .application
application/vnd.ms-xpsdocument   .xps
application/xaml+xml             .xaml

(taken from here: http://www.xbap.org/faq.html )

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Firefox runs XBAPs by using a dll from the .Net 3.5 Installer, and since Windows 7 comes with 3.5 already installed, this dll isn't available

Solution is to copy the file C:\WINDOWS\Microsoft.NET\Framework\v3.5\Windows Presentation Foundation\NPWPF.dll from an XP machine to C:\Program Files (x86)\Mozilla Firefox\plugins (if the plugin folder doesn't exist, create it)