Not panicking yet, but... I have a simple aspx page with a FileUpload for saving and image file to a database. The image is displayed using a Silverlight control (which is not important because it fails even if I use a plain asp:Image).
After the user uploads the file, a button is pressed to Save it to Session. Then a second save button is pressed to store it in the backend. When the page is reloaded, the image is retrieved and saved to a 'cache' on the web server ( folder 'images'). A Uri is constructed for the file, which is then set to the source of the image embedded in the Silverlight control. So the image control should be pointing to the file in the cache.
The peculiar thing is that this contraption works fine in Visual Studio 2010, but it fails when it is deployed to the server. I suspect it has to do with the Server.MapPath line but I cannot prove it. I observe that the file gets written to the physical server path, but I cannot see the file when I browse the web site within IIS7, so I also suspect the problem may have to do with my configuration of the IIS7 web site.