Hi Andr3w,
I think you're coming up against two problems here, both stemming from using IIS rather than the web server built into VWD. If you're using Windows Vista, that's IIS7 too. Please check out how to set up the chapter samples using IIS 6 in the new appendix B I wrote which you can downlaod from my website at
http://www.hmobius.com/downloads.aspx
While you're reading through that that the reason you get the parser error message you quote is becuase in IIS you've created a virtual directory that contains more than one web.config files (in different directories).
So for example in Chapter 12 (I'm assuming C# here), you should be creating a virtual directory on Begin\Chapter12\PDA or Begin\Chapter12\WroxUnited rather than Begin\Chapter12.
The same applies for the rest of the chapters.
Hope that helps.
Dan
Dan Maharry
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