IIS aways returns an empty page
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I am deploying a site built as a set of projects in a solution which is deployed as a series of websites (one project = one url).

The coding lanague is c# and the site uses a mssql db accessed via linq.

Everything works ok on the development server but at the moment, all pages with dynamically created elements (i.e all <asp> and custom tags) output a blank page with the following source code. Static pages (standard html and aspx) display correctly.

    <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
    <HTML><HEAD>
    <META content="text/html; charset=windows-1252" http-equiv=Content-Type></HEAD>
    <BODY></BODY></HTML>

I normally work with php on LAMP and this behaviour is unlike anything I've seen in that setup. I need some fresh ideas on causes / resolution of this error (preferably step by step / tutorial links - like I say IIS/c#.net is not my normal enviroment).

Things I have tried with no effect whatsoever:

 - altering permissions on site folders
 - altering web.config settings
 - Redeploying site files via copy / paste and the vb publish option with various settings
 - Plus a whole ton (over two days so far) of internet research

Thanks for all replies.